diff --git a/src/adapters/Z3ExpressionAdapter.cpp b/src/adapters/Z3ExpressionAdapter.cpp
new file mode 100644
index 000000000..60b4e8e1c
--- /dev/null
+++ b/src/adapters/Z3ExpressionAdapter.cpp
@@ -0,0 +1,288 @@
+
+#include "Z3ExpressionAdapter.h"
+#include "src/storage/expressions/Expressions.h"
+#include "src/storage/expressions/ExpressionManager.h"
+#include "src/utility/macros.h"
+#include "src/exceptions/ExpressionEvaluationException.h"
+#include "src/exceptions/InvalidTypeException.h"
+#include "src/exceptions/NotImplementedException.h"
+namespace storm {
+    namespace adapters {
+
+#ifdef STORM_HAVE_Z3
+            Z3ExpressionAdapter::Z3ExpressionAdapter(storm::expressions::ExpressionManager& manager, z3::context& context) : manager(manager), context(context), additionalAssertions(), variableToExpressionMapping() {
+                // Intentionally left empty.
+            }
+            
+            z3::expr Z3ExpressionAdapter::translateExpression(storm::expressions::Expression const& expression) {
+                STORM_LOG_ASSERT(expression.getManager() == this->manager, "Invalid expression for solver.");
+                z3::expr result = boost::any_cast<z3::expr>(expression.getBaseExpression().accept(*this));
+                
+                for (z3::expr const& assertion : additionalAssertions) {
+                    result = result && assertion;
+                }
+                additionalAssertions.clear();
+
+                return result;
+            }
+            
+            z3::expr Z3ExpressionAdapter::translateExpression(storm::expressions::Variable const& variable) {
+                STORM_LOG_ASSERT(variable.getManager() == this->manager, "Invalid expression for solver.");
+                
+                auto const& variableExpressionPair = variableToExpressionMapping.find(variable);
+                if (variableExpressionPair == variableToExpressionMapping.end()) {
+                    return createVariable(variable);
+                }
+
+                return variableExpressionPair->second;
+            }
+            
+            storm::expressions::Variable const& Z3ExpressionAdapter::getVariable(z3::func_decl z3Declaration) {
+                auto const& declarationVariablePair = declarationToVariableMapping.find(z3Declaration);
+                STORM_LOG_ASSERT(declarationVariablePair != declarationToVariableMapping.end(), "Unable to find declaration.");
+                return declarationVariablePair->second;
+            }
+            
+            storm::expressions::Expression Z3ExpressionAdapter::translateExpression(z3::expr const& expr) {
+                if (expr.is_app()) {
+                        switch (expr.decl().decl_kind()) {
+                            case Z3_OP_TRUE:
+                                    return manager.boolean(true);
+                            case Z3_OP_FALSE:
+                                    return manager.boolean(false);
+                            case Z3_OP_EQ:
+                                    return this->translateExpression(expr.arg(0)) == this->translateExpression(expr.arg(1));
+                            case Z3_OP_ITE:
+                                    return storm::expressions::ite(this->translateExpression(expr.arg(0)), this->translateExpression(expr.arg(1)), this->translateExpression(expr.arg(2)));
+                            case Z3_OP_AND: {
+                                    unsigned args = expr.num_args();
+                                    STORM_LOG_THROW(args != 0, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. 0-ary AND is assumed to be an error.");
+                                    if (args == 1) {
+                                            return this->translateExpression(expr.arg(0));
+                                    } else {
+                                            storm::expressions::Expression retVal = this->translateExpression(expr.arg(0));
+                                            for (unsigned i = 1; i < args; i++) {
+                                                    retVal = retVal && this->translateExpression(expr.arg(i));
+                                            }
+                                            return retVal;
+                                    }
+                            }
+                            case Z3_OP_OR: {
+                                    unsigned args = expr.num_args();
+                                    STORM_LOG_THROW(args != 0, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. 0-ary OR is assumed to be an error.");
+                                    if (args == 1) {
+                                            return this->translateExpression(expr.arg(0));
+                                    } else {
+                                            storm::expressions::Expression retVal = this->translateExpression(expr.arg(0));
+                                            for (unsigned i = 1; i < args; i++) {
+                                                    retVal = retVal || this->translateExpression(expr.arg(i));
+                                            }
+                                            return retVal;
+                                    }
+                            }
+                            case Z3_OP_IFF:
+                                    return storm::expressions::iff(this->translateExpression(expr.arg(0)), this->translateExpression(expr.arg(1)));
+                            case Z3_OP_XOR:
+                                    return this->translateExpression(expr.arg(0)) ^ this->translateExpression(expr.arg(1));
+                            case Z3_OP_NOT:
+                                    return !this->translateExpression(expr.arg(0));
+                            case Z3_OP_IMPLIES:
+                                    return storm::expressions::implies(this->translateExpression(expr.arg(0)), this->translateExpression(expr.arg(1)));
+                            case Z3_OP_LE:
+                                    return this->translateExpression(expr.arg(0)) <= this->translateExpression(expr.arg(1));
+                            case Z3_OP_GE:
+                                    return this->translateExpression(expr.arg(0)) >= this->translateExpression(expr.arg(1));
+                            case Z3_OP_LT:
+                                    return this->translateExpression(expr.arg(0)) < this->translateExpression(expr.arg(1));
+                            case Z3_OP_GT:
+                                    return this->translateExpression(expr.arg(0)) > this->translateExpression(expr.arg(1));
+                            case Z3_OP_ADD:
+                                    return this->translateExpression(expr.arg(0)) + this->translateExpression(expr.arg(1));
+                            case Z3_OP_SUB:
+                                    return this->translateExpression(expr.arg(0)) - this->translateExpression(expr.arg(1));
+                            case Z3_OP_UMINUS:
+                                    return -this->translateExpression(expr.arg(0));
+                            case Z3_OP_MUL:
+                                    return this->translateExpression(expr.arg(0)) * this->translateExpression(expr.arg(1));
+                            case Z3_OP_DIV:
+                                    return this->translateExpression(expr.arg(0)) / this->translateExpression(expr.arg(1));
+                            case Z3_OP_IDIV:
+                                    return this->translateExpression(expr.arg(0)) / this->translateExpression(expr.arg(1));
+                            case Z3_OP_ANUM:
+                                // Arithmetic numeral.
+                                if (expr.is_int() && expr.is_const()) {
+                                    long long value;
+                                    if (Z3_get_numeral_int64(expr.ctx(), expr, &value)) {
+                                        return manager.integer(value);
+                                    } else {
+                                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Expression is constant integer and value does not fit into 64-bit integer.");
+                                    }
+                                } else if (expr.is_real() && expr.is_const()) {
+                                    long long num;
+                                    long long den;
+                                    if (Z3_get_numeral_rational_int64(expr.ctx(), expr, &num, &den)) {
+                                        return manager.rational(static_cast<double>(num) / static_cast<double>(den));
+                                    } else {
+                                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Expression is constant real and value does not fit into a fraction with 64-bit integer numerator and denominator.");
+                                    }
+                                }
+                            case Z3_OP_UNINTERPRETED:
+                                // Currently, we only support uninterpreted constant functions.
+                                STORM_LOG_THROW(expr.is_const(), storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Encountered non-constant uninterpreted function.");
+                                return manager.getVariable(expr.decl().name().str()).getExpression();
+                            default:
+                                STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Encountered unhandled Z3_decl_kind " << expr.decl().kind() <<".");
+                                break;
+                        }
+                    } else {
+                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Encountered unknown expression type.");
+                    }
+            }
+
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::BinaryBooleanFunctionExpression const& expression)  {
+                z3::expr leftResult = boost::any_cast<z3::expr>(expression.getFirstOperand()->accept(*this));
+                z3::expr rightResult = boost::any_cast<z3::expr>(expression.getSecondOperand()->accept(*this));
+                
+                switch(expression.getOperatorType()) {
+					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::And:
+                        return leftResult && rightResult;
+					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Or:
+                        return leftResult || rightResult;
+					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Xor:
+						return z3::expr(context, Z3_mk_xor(context, leftResult, rightResult));
+					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Implies:
+						return z3::expr(context, Z3_mk_implies(context, leftResult, rightResult));
+					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Iff:
+						return z3::expr(context, Z3_mk_iff(context, leftResult, rightResult));
+                    default:
+                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown boolean binary operator '" << static_cast<int>(expression.getOperatorType()) << "' in expression " << expression << ".");
+                }
+                
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::BinaryNumericalFunctionExpression const& expression)  {
+                z3::expr leftResult = boost::any_cast<z3::expr>(expression.getFirstOperand()->accept(*this));
+                z3::expr rightResult = boost::any_cast<z3::expr>(expression.getSecondOperand()->accept(*this));
+        
+                switch(expression.getOperatorType()) {
+					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Plus:
+                        return leftResult + rightResult;
+					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Minus:
+                        return leftResult - rightResult;
+					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Times:
+                        return leftResult * rightResult;
+					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Divide:
+                        return leftResult / rightResult;
+					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Min:
+                        return ite(leftResult <= rightResult, leftResult, rightResult);
+					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Max:
+                        return ite(leftResult >= rightResult, leftResult, rightResult);
+                    default:
+                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown numerical binary operator '" << static_cast<int>(expression.getOperatorType()) << "' in expression " << expression << ".");
+                }
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::BinaryRelationExpression const& expression)  {
+                z3::expr leftResult = boost::any_cast<z3::expr>(expression.getFirstOperand()->accept(*this));
+                z3::expr rightResult = boost::any_cast<z3::expr>(expression.getSecondOperand()->accept(*this));
+    
+                switch(expression.getRelationType()) {
+					case storm::expressions::BinaryRelationExpression::RelationType::Equal:
+                        return leftResult == rightResult;
+					case storm::expressions::BinaryRelationExpression::RelationType::NotEqual:
+                        return leftResult != rightResult;
+					case storm::expressions::BinaryRelationExpression::RelationType::Less:
+                        return leftResult < rightResult;
+					case storm::expressions::BinaryRelationExpression::RelationType::LessOrEqual:
+                        return leftResult <= rightResult;
+					case storm::expressions::BinaryRelationExpression::RelationType::Greater:
+                        return leftResult > rightResult;
+					case storm::expressions::BinaryRelationExpression::RelationType::GreaterOrEqual:
+                        return leftResult >= rightResult;
+                    default:
+                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown boolean binary operator '" << static_cast<int>(expression.getRelationType()) << "' in expression " << expression << ".");
+                }    
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::BooleanLiteralExpression const& expression)  {
+                return context.bool_val(expression.getValue());
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::DoubleLiteralExpression const& expression)  {
+                std::stringstream fractionStream;
+                fractionStream << expression.getValue();
+                return context.real_val(fractionStream.str().c_str());
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::IntegerLiteralExpression const& expression)  {
+                return context.int_val(static_cast<int>(expression.getValue()));
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::UnaryBooleanFunctionExpression const& expression)  {
+                z3::expr childResult = boost::any_cast<z3::expr>(expression.getOperand()->accept(*this));
+                
+                switch (expression.getOperatorType()) {
+					case storm::expressions::UnaryBooleanFunctionExpression::OperatorType::Not:
+                        return !childResult;
+                    default:
+                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown boolean binary operator '" << static_cast<int>(expression.getOperatorType()) << "' in expression " << expression << ".");
+                }    
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::UnaryNumericalFunctionExpression const& expression)  {
+                z3::expr childResult = boost::any_cast<z3::expr>(expression.getOperand()->accept(*this));
+                
+                switch(expression.getOperatorType()) {
+					case storm::expressions::UnaryNumericalFunctionExpression::OperatorType::Minus:
+                        return 0 - childResult;
+					case storm::expressions::UnaryNumericalFunctionExpression::OperatorType::Floor: {
+                        storm::expressions::Variable freshAuxiliaryVariable = manager.declareFreshVariable(manager.getIntegerType(), true);
+                        z3::expr floorVariable = context.int_const(freshAuxiliaryVariable.getName().c_str());
+						additionalAssertions.push_back(z3::expr(context, Z3_mk_int2real(context, floorVariable)) <= childResult && childResult < (z3::expr(context, Z3_mk_int2real(context, floorVariable)) + 1));
+						return floorVariable;
+					}
+					case storm::expressions::UnaryNumericalFunctionExpression::OperatorType::Ceil:{
+                        storm::expressions::Variable freshAuxiliaryVariable = manager.declareFreshVariable(manager.getIntegerType(), true);
+                        z3::expr ceilVariable = context.int_const(freshAuxiliaryVariable.getName().c_str());
+						additionalAssertions.push_back(z3::expr(context, Z3_mk_int2real(context, ceilVariable)) - 1 <= childResult && childResult < z3::expr(context, Z3_mk_int2real(context, ceilVariable)));
+						return ceilVariable;
+					}
+                    default: STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown numerical unary operator '" << static_cast<int>(expression.getOperatorType()) << "'.");
+                }
+            }
+
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::IfThenElseExpression const& expression)  {
+                z3::expr conditionResult = boost::any_cast<z3::expr>(expression.getCondition()->accept(*this));
+                z3::expr thenResult = boost::any_cast<z3::expr>(expression.getThenExpression()->accept(*this));
+                z3::expr elseResult = boost::any_cast<z3::expr>(expression.getElseExpression()->accept(*this));
+                return z3::expr(context, Z3_mk_ite(context, conditionResult, thenResult, elseResult));
+            }
+            
+            boost::any Z3ExpressionAdapter::visit(storm::expressions::VariableExpression const& expression)  {
+                return this->translateExpression(expression.getVariable());
+            }
+                        
+
+            z3::expr Z3ExpressionAdapter::createVariable(storm::expressions::Variable const& variable) {
+                z3::expr z3Variable(context);
+                if (variable.getType().isBooleanType()) {
+                    z3Variable = context.bool_const(variable.getName().c_str());
+                } else if (variable.getType().isIntegerType()) {
+                    z3Variable = context.int_const(variable.getName().c_str());
+                } else if (variable.getType().isBitVectorType()) {
+                    z3Variable = context.bv_const(variable.getName().c_str(), variable.getType().getWidth());
+                } else if (variable.getType().isRationalType()) {
+                    z3Variable = context.real_const(variable.getName().c_str());
+                } else {
+                    STORM_LOG_THROW(false, storm::exceptions::InvalidTypeException, "Encountered variable '" << variable.getName() << "' with unknown type while trying to create solver variables.");
+                }
+                variableToExpressionMapping.insert(std::make_pair(variable, z3Variable));
+                declarationToVariableMapping.insert(std::make_pair(z3Variable.decl(), variable));
+                return z3Variable;
+            }
+
+
+#endif
+    } // namespace adapters
+} // namespace storm
+
diff --git a/src/adapters/Z3ExpressionAdapter.h b/src/adapters/Z3ExpressionAdapter.h
index 419bab938..70180a241 100644
--- a/src/adapters/Z3ExpressionAdapter.h
+++ b/src/adapters/Z3ExpressionAdapter.h
@@ -2,20 +2,17 @@
 #define STORM_ADAPTERS_Z3EXPRESSIONADAPTER_H_
 
 #include <unordered_map>
+#include <vector>
 
+#include "storm-config.h"
 // Include the headers of Z3 only if it is available.
 #ifdef STORM_HAVE_Z3
 #include "z3++.h"
 #include "z3.h"
 #endif
 
-#include "storm-config.h"
-#include "src/storage/expressions/Expressions.h"
-#include "src/storage/expressions/ExpressionManager.h"
-#include "src/utility/macros.h"
-#include "src/exceptions/ExpressionEvaluationException.h"
-#include "src/exceptions/InvalidTypeException.h"
-#include "src/exceptions/NotImplementedException.h"
+#include "src/storage/expressions/Variable.h"
+#include "src/storage/expressions/ExpressionVisitor.h"
 
 namespace storm {
     namespace adapters {
@@ -30,275 +27,51 @@ namespace storm {
              * @param context A reference to the Z3 context over which to build the expressions. The lifetime of the
              * context needs to be guaranteed as long as the instance of this adapter is used.
              */
-            Z3ExpressionAdapter(storm::expressions::ExpressionManager& manager, z3::context& context) : manager(manager), context(context), additionalAssertions(), variableToExpressionMapping() {
-                // Intentionally left empty.
-            }
-            
+            Z3ExpressionAdapter(storm::expressions::ExpressionManager& manager, z3::context& context);
             /*!
              * Translates the given expression to an equivalent expression for Z3.
 			 *
              * @param expression The expression to translate.
              * @return An equivalent expression for Z3.
              */
-            z3::expr translateExpression(storm::expressions::Expression const& expression) {
-                STORM_LOG_ASSERT(expression.getManager() == this->manager, "Invalid expression for solver.");
-                z3::expr result = boost::any_cast<z3::expr>(expression.getBaseExpression().accept(*this));
-                
-                for (z3::expr const& assertion : additionalAssertions) {
-                    result = result && assertion;
-                }
-                additionalAssertions.clear();
-
-                return result;
-            }
-            
+            z3::expr translateExpression(storm::expressions::Expression const& expression);            
             /*!
              * Translates the given variable to an equivalent expression for Z3.
              *
              * @param variable The variable to translate.
              * @return An equivalent expression for Z3.
              */
-            z3::expr translateExpression(storm::expressions::Variable const& variable) {
-                STORM_LOG_ASSERT(variable.getManager() == this->manager, "Invalid expression for solver.");
-                
-                auto const& variableExpressionPair = variableToExpressionMapping.find(variable);
-                if (variableExpressionPair == variableToExpressionMapping.end()) {
-                    return createVariable(variable);
-                }
-
-                return variableExpressionPair->second;
-            }
+            z3::expr translateExpression(storm::expressions::Variable const& variable);
+            
             
+            storm::expressions::Expression translateExpression(z3::expr const& expr);
             /*!
              * Finds the counterpart to the given z3 variable declaration.
              *
              * @param z3Declaration The declaration for which to find the equivalent.
              * @return The equivalent counterpart.
              */
-            storm::expressions::Variable const& getVariable(z3::func_decl z3Declaration) {
-                auto const& declarationVariablePair = declarationToVariableMapping.find(z3Declaration);
-                STORM_LOG_ASSERT(declarationVariablePair != declarationToVariableMapping.end(), "Unable to find declaration.");
-                return declarationVariablePair->second;
-            }
-            
-			storm::expressions::Expression translateExpression(z3::expr const& expr) {
-				if (expr.is_app()) {
-					switch (expr.decl().decl_kind()) {
-						case Z3_OP_TRUE:
-							return manager.boolean(true);
-						case Z3_OP_FALSE:
-							return manager.boolean(false);
-						case Z3_OP_EQ:
-							return this->translateExpression(expr.arg(0)) == this->translateExpression(expr.arg(1));
-						case Z3_OP_ITE:
-							return storm::expressions::ite(this->translateExpression(expr.arg(0)), this->translateExpression(expr.arg(1)), this->translateExpression(expr.arg(2)));
-						case Z3_OP_AND: {
-							unsigned args = expr.num_args();
-							STORM_LOG_THROW(args != 0, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. 0-ary AND is assumed to be an error.");
-							if (args == 1) {
-								return this->translateExpression(expr.arg(0));
-							} else {
-								storm::expressions::Expression retVal = this->translateExpression(expr.arg(0));
-								for (unsigned i = 1; i < args; i++) {
-									retVal = retVal && this->translateExpression(expr.arg(i));
-								}
-								return retVal;
-							}
-						}
-						case Z3_OP_OR: {
-							unsigned args = expr.num_args();
-							STORM_LOG_THROW(args != 0, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. 0-ary OR is assumed to be an error.");
-							if (args == 1) {
-								return this->translateExpression(expr.arg(0));
-							} else {
-								storm::expressions::Expression retVal = this->translateExpression(expr.arg(0));
-								for (unsigned i = 1; i < args; i++) {
-									retVal = retVal || this->translateExpression(expr.arg(i));
-								}
-								return retVal;
-							}
-						}
-						case Z3_OP_IFF:
-							return storm::expressions::iff(this->translateExpression(expr.arg(0)), this->translateExpression(expr.arg(1)));
-						case Z3_OP_XOR:
-							return this->translateExpression(expr.arg(0)) ^ this->translateExpression(expr.arg(1));
-						case Z3_OP_NOT:
-							return !this->translateExpression(expr.arg(0));
-						case Z3_OP_IMPLIES:
-							return storm::expressions::implies(this->translateExpression(expr.arg(0)), this->translateExpression(expr.arg(1)));
-						case Z3_OP_LE:
-							return this->translateExpression(expr.arg(0)) <= this->translateExpression(expr.arg(1));
-						case Z3_OP_GE:
-							return this->translateExpression(expr.arg(0)) >= this->translateExpression(expr.arg(1));
-						case Z3_OP_LT:
-							return this->translateExpression(expr.arg(0)) < this->translateExpression(expr.arg(1));
-						case Z3_OP_GT:
-							return this->translateExpression(expr.arg(0)) > this->translateExpression(expr.arg(1));
-						case Z3_OP_ADD:
-							return this->translateExpression(expr.arg(0)) + this->translateExpression(expr.arg(1));
-						case Z3_OP_SUB:
-							return this->translateExpression(expr.arg(0)) - this->translateExpression(expr.arg(1));
-						case Z3_OP_UMINUS:
-							return -this->translateExpression(expr.arg(0));
-						case Z3_OP_MUL:
-							return this->translateExpression(expr.arg(0)) * this->translateExpression(expr.arg(1));
-						case Z3_OP_DIV:
-							return this->translateExpression(expr.arg(0)) / this->translateExpression(expr.arg(1));
-						case Z3_OP_IDIV:
-							return this->translateExpression(expr.arg(0)) / this->translateExpression(expr.arg(1));
-						case Z3_OP_ANUM:
-							// Arithmetic numeral.
-							if (expr.is_int() && expr.is_const()) {
-								long long value;
-								if (Z3_get_numeral_int64(expr.ctx(), expr, &value)) {
-									return manager.integer(value);
-								} else {
-									STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Expression is constant integer and value does not fit into 64-bit integer.");
-								}
-							} else if (expr.is_real() && expr.is_const()) {
-								long long num;
-								long long den;
-								if (Z3_get_numeral_rational_int64(expr.ctx(), expr, &num, &den)) {
-									return manager.rational(static_cast<double>(num) / static_cast<double>(den));
-								} else {
-									STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Expression is constant real and value does not fit into a fraction with 64-bit integer numerator and denominator.");
-								}
-							}
-						case Z3_OP_UNINTERPRETED:
-							// Currently, we only support uninterpreted constant functions.
-							STORM_LOG_THROW(expr.is_const(), storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Encountered non-constant uninterpreted function.");
-                            return manager.getVariable(expr.decl().name().str()).getExpression();
-						default:
-							STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Encountered unhandled Z3_decl_kind " << expr.decl().kind() <<".");
-							break;
-					}
-				} else {
-					STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Failed to convert Z3 expression. Encountered unknown expression type.");
-				}
-			}
+            storm::expressions::Variable const& getVariable(z3::func_decl z3Declaration);
 
-            virtual boost::any visit(storm::expressions::BinaryBooleanFunctionExpression const& expression) override {
-                z3::expr leftResult = boost::any_cast<z3::expr>(expression.getFirstOperand()->accept(*this));
-                z3::expr rightResult = boost::any_cast<z3::expr>(expression.getSecondOperand()->accept(*this));
-                
-                switch(expression.getOperatorType()) {
-					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::And:
-                        return leftResult && rightResult;
-					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Or:
-                        return leftResult || rightResult;
-					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Xor:
-						return z3::expr(context, Z3_mk_xor(context, leftResult, rightResult));
-					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Implies:
-						return z3::expr(context, Z3_mk_implies(context, leftResult, rightResult));
-					case storm::expressions::BinaryBooleanFunctionExpression::OperatorType::Iff:
-						return z3::expr(context, Z3_mk_iff(context, leftResult, rightResult));
-                    default:
-                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown boolean binary operator '" << static_cast<int>(expression.getOperatorType()) << "' in expression " << expression << ".");
-                }
-                
-            }
+            virtual boost::any visit(storm::expressions::BinaryBooleanFunctionExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::BinaryNumericalFunctionExpression const& expression) override {
-                z3::expr leftResult = boost::any_cast<z3::expr>(expression.getFirstOperand()->accept(*this));
-                z3::expr rightResult = boost::any_cast<z3::expr>(expression.getSecondOperand()->accept(*this));
-        
-                switch(expression.getOperatorType()) {
-					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Plus:
-                        return leftResult + rightResult;
-					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Minus:
-                        return leftResult - rightResult;
-					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Times:
-                        return leftResult * rightResult;
-					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Divide:
-                        return leftResult / rightResult;
-					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Min:
-                        return ite(leftResult <= rightResult, leftResult, rightResult);
-					case storm::expressions::BinaryNumericalFunctionExpression::OperatorType::Max:
-                        return ite(leftResult >= rightResult, leftResult, rightResult);
-                    default:
-                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown numerical binary operator '" << static_cast<int>(expression.getOperatorType()) << "' in expression " << expression << ".");
-                }
-            }
+            virtual boost::any visit(storm::expressions::BinaryNumericalFunctionExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::BinaryRelationExpression const& expression) override {
-                z3::expr leftResult = boost::any_cast<z3::expr>(expression.getFirstOperand()->accept(*this));
-                z3::expr rightResult = boost::any_cast<z3::expr>(expression.getSecondOperand()->accept(*this));
-    
-                switch(expression.getRelationType()) {
-					case storm::expressions::BinaryRelationExpression::RelationType::Equal:
-                        return leftResult == rightResult;
-					case storm::expressions::BinaryRelationExpression::RelationType::NotEqual:
-                        return leftResult != rightResult;
-					case storm::expressions::BinaryRelationExpression::RelationType::Less:
-                        return leftResult < rightResult;
-					case storm::expressions::BinaryRelationExpression::RelationType::LessOrEqual:
-                        return leftResult <= rightResult;
-					case storm::expressions::BinaryRelationExpression::RelationType::Greater:
-                        return leftResult > rightResult;
-					case storm::expressions::BinaryRelationExpression::RelationType::GreaterOrEqual:
-                        return leftResult >= rightResult;
-                    default:
-                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown boolean binary operator '" << static_cast<int>(expression.getRelationType()) << "' in expression " << expression << ".");
-                }    
-            }
+            virtual boost::any visit(storm::expressions::BinaryRelationExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::BooleanLiteralExpression const& expression) override {
-                return context.bool_val(expression.getValue());
-            }
+            virtual boost::any visit(storm::expressions::BooleanLiteralExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::DoubleLiteralExpression const& expression) override {
-                std::stringstream fractionStream;
-                fractionStream << expression.getValue();
-                return context.real_val(fractionStream.str().c_str());
-            }
+            virtual boost::any visit(storm::expressions::DoubleLiteralExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::IntegerLiteralExpression const& expression) override {
-                return context.int_val(static_cast<int>(expression.getValue()));
-            }
+            virtual boost::any visit(storm::expressions::IntegerLiteralExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::UnaryBooleanFunctionExpression const& expression) override {
-                z3::expr childResult = boost::any_cast<z3::expr>(expression.getOperand()->accept(*this));
-                
-                switch (expression.getOperatorType()) {
-					case storm::expressions::UnaryBooleanFunctionExpression::OperatorType::Not:
-                        return !childResult;
-                    default:
-                        STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown boolean binary operator '" << static_cast<int>(expression.getOperatorType()) << "' in expression " << expression << ".");
-                }    
-            }
+            virtual boost::any visit(storm::expressions::UnaryBooleanFunctionExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::UnaryNumericalFunctionExpression const& expression) override {
-                z3::expr childResult = boost::any_cast<z3::expr>(expression.getOperand()->accept(*this));
-                
-                switch(expression.getOperatorType()) {
-					case storm::expressions::UnaryNumericalFunctionExpression::OperatorType::Minus:
-                        return 0 - childResult;
-					case storm::expressions::UnaryNumericalFunctionExpression::OperatorType::Floor: {
-                        storm::expressions::Variable freshAuxiliaryVariable = manager.declareFreshVariable(manager.getIntegerType(), true);
-                        z3::expr floorVariable = context.int_const(freshAuxiliaryVariable.getName().c_str());
-						additionalAssertions.push_back(z3::expr(context, Z3_mk_int2real(context, floorVariable)) <= childResult && childResult < (z3::expr(context, Z3_mk_int2real(context, floorVariable)) + 1));
-						return floorVariable;
-					}
-					case storm::expressions::UnaryNumericalFunctionExpression::OperatorType::Ceil:{
-                        storm::expressions::Variable freshAuxiliaryVariable = manager.declareFreshVariable(manager.getIntegerType(), true);
-                        z3::expr ceilVariable = context.int_const(freshAuxiliaryVariable.getName().c_str());
-						additionalAssertions.push_back(z3::expr(context, Z3_mk_int2real(context, ceilVariable)) - 1 <= childResult && childResult < z3::expr(context, Z3_mk_int2real(context, ceilVariable)));
-						return ceilVariable;
-					}
-                    default: STORM_LOG_THROW(false, storm::exceptions::ExpressionEvaluationException, "Cannot evaluate expression: unknown numerical unary operator '" << static_cast<int>(expression.getOperatorType()) << "'.");
-                }
-            }
+            virtual boost::any visit(storm::expressions::UnaryNumericalFunctionExpression const& expression) override;
 
-			virtual boost::any visit(storm::expressions::IfThenElseExpression const& expression) override {
-                z3::expr conditionResult = boost::any_cast<z3::expr>(expression.getCondition()->accept(*this));
-                z3::expr thenResult = boost::any_cast<z3::expr>(expression.getThenExpression()->accept(*this));
-                z3::expr elseResult = boost::any_cast<z3::expr>(expression.getElseExpression()->accept(*this));
-				return z3::expr(context, Z3_mk_ite(context, conditionResult, thenResult, elseResult));
-			}
+            virtual boost::any visit(storm::expressions::IfThenElseExpression const& expression) override;
             
-			virtual boost::any visit(storm::expressions::VariableExpression const& expression) override {
-                return this->translateExpression(expression.getVariable());
-            }
+            virtual boost::any visit(storm::expressions::VariableExpression const& expression) override;
 
         private:
             /*!
@@ -306,25 +79,7 @@ namespace storm {
              *
              * @param variable The variable for which to create a Z3 counterpart.
              */
-            z3::expr createVariable(storm::expressions::Variable const& variable) {
-                z3::expr z3Variable(context);
-                if (variable.getType().isBooleanType()) {
-                    z3Variable = context.bool_const(variable.getName().c_str());
-                } else if (variable.getType().isIntegerType()) {
-                    z3Variable = context.int_const(variable.getName().c_str());
-                } else if (variable.getType().isBitVectorType()) {
-                    z3Variable = context.bv_const(variable.getName().c_str(), variable.getType().getWidth());
-                } else if (variable.getType().isRationalType()) {
-                    z3Variable = context.real_const(variable.getName().c_str());
-                } else {
-                    STORM_LOG_THROW(false, storm::exceptions::InvalidTypeException, "Encountered variable '" << variable.getName() << "' with unknown type while trying to create solver variables.");
-                }
-                variableToExpressionMapping.insert(std::make_pair(variable, z3Variable));
-                declarationToVariableMapping.insert(std::make_pair(z3Variable.decl(), variable));
-                return z3Variable;
-            }
-
-
+            z3::expr createVariable(storm::expressions::Variable const& variable);
             // The manager that can be used to build expressions.
             storm::expressions::ExpressionManager& manager;
 
@@ -333,7 +88,7 @@ namespace storm {
 
             // A vector of assertions that need to be kept separate, because they were only implicitly part of an
             // assertion that was added.
-			std::vector<z3::expr> additionalAssertions;
+            std::vector<z3::expr> additionalAssertions;
 
             // A mapping from variables to their Z3 equivalent.
             std::unordered_map<storm::expressions::Variable, z3::expr> variableToExpressionMapping;
diff --git a/src/models/sparse/Model.h b/src/models/sparse/Model.h
index 4d1901d1f..83173ab63 100644
--- a/src/models/sparse/Model.h
+++ b/src/models/sparse/Model.h
@@ -11,6 +11,8 @@
 #include "src/storage/BitVector.h"
 #include "src/storage/SparseMatrix.h"
 #include "src/utility/OsDetection.h"
+// Forward declarations
+ 
 
 namespace storm {
     namespace models {
@@ -19,6 +21,7 @@ namespace storm {
             // The type used for storing a set of labels.
             typedef boost::container::flat_set<uint_fast64_t> LabelSet;
             
+           
             /*!
              * Base class for all sparse models.
              */
diff --git a/src/models/sparse/StateLabeling.cpp b/src/models/sparse/StateLabeling.cpp
index e23fd7b4c..3f1504496 100644
--- a/src/models/sparse/StateLabeling.cpp
+++ b/src/models/sparse/StateLabeling.cpp
@@ -1,4 +1,8 @@
 #include "src/models/sparse/StateLabeling.h"
+#include "src/storage/BitVector.h"
+#include "src/exceptions/OutOfRangeException.h"
+#include "src/exceptions/InvalidArgumentException.h"
+
 
 namespace storm {
     namespace models {
diff --git a/src/models/sparse/StateLabeling.h b/src/models/sparse/StateLabeling.h
index 072c8ed3d..c7b3411a7 100644
--- a/src/models/sparse/StateLabeling.h
+++ b/src/models/sparse/StateLabeling.h
@@ -6,17 +6,16 @@
 #include <ostream>
 
 #include "src/storage/sparse/StateType.h"
-#include "src/storage/BitVector.h"
-#include "src/exceptions/OutOfRangeException.h"
-#include "src/exceptions/InvalidArgumentException.h"
 
+#include "src/storage/BitVector.h"
 #include "src/utility/macros.h"
 #include "src/utility/OsDetection.h"
 
+            
 namespace storm {
     namespace models {
         namespace sparse {
-            
+
             /*!
              * This class manages the labeling of the state space with a number of (atomic) labels.
              */
diff --git a/src/parser/PrismParser.h b/src/parser/PrismParser.h
index 8d6c10ac0..22510b4af 100644
--- a/src/parser/PrismParser.h
+++ b/src/parser/PrismParser.h
@@ -9,12 +9,17 @@
 #include "src/parser/SpiritParserDefinitions.h"
 #include "src/parser/ExpressionParser.h"
 #include "src/storage/prism/Program.h"
-#include "src/storage/expressions/ExpressionManager.h"
 #include "src/storage/expressions/Expression.h"
 #include "src/storage/expressions/Expressions.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/WrongFormatException.h"
 
+namespace storm {
+    namespace expressions {
+        class ExpressionManager;
+    }
+}
+
 namespace storm {
     namespace parser {
         // A class that stores information about the parsed program.
diff --git a/src/solver/GlpkLpSolver.cpp b/src/solver/GlpkLpSolver.cpp
index d88fdb407..fd36a0bff 100644
--- a/src/solver/GlpkLpSolver.cpp
+++ b/src/solver/GlpkLpSolver.cpp
@@ -8,6 +8,9 @@
 
 #include "src/settings/SettingsManager.h"
 #include "src/utility/macros.h"
+#include "src/storage/expressions/Expression.h"
+#include "src/storage/expressions/ExpressionManager.h"
+
 #include "src/exceptions/InvalidAccessException.h"
 #include "src/exceptions/InvalidStateException.h"
 
diff --git a/src/solver/GlpkLpSolver.h b/src/solver/GlpkLpSolver.h
index 130d59a9b..4717b5d97 100644
--- a/src/solver/GlpkLpSolver.h
+++ b/src/solver/GlpkLpSolver.h
@@ -1,6 +1,7 @@
 #ifndef STORM_SOLVER_GLPKLPSOLVER_H_
 #define STORM_SOLVER_GLPKLPSOLVER_H_
 
+#include <map>
 #include "src/solver/LpSolver.h"
 #include "src/exceptions/NotImplementedException.h"
 
diff --git a/src/solver/GurobiLpSolver.cpp b/src/solver/GurobiLpSolver.cpp
index 50e36b809..b6c0202f7 100644
--- a/src/solver/GurobiLpSolver.cpp
+++ b/src/solver/GurobiLpSolver.cpp
@@ -7,6 +7,9 @@
 
 #include "src/settings/SettingsManager.h"
 #include "src/utility/macros.h"
+#include "src/storage/expressions/Expression.h"
+#include "src/storage/expressions/ExpressionManager.h"
+
 #include "src/exceptions/InvalidStateException.h"
 #include "src/exceptions/InvalidAccessException.h"
 
diff --git a/src/solver/GurobiLpSolver.h b/src/solver/GurobiLpSolver.h
index 21e4e9e53..186715922 100644
--- a/src/solver/GurobiLpSolver.h
+++ b/src/solver/GurobiLpSolver.h
@@ -1,6 +1,7 @@
 #ifndef STORM_SOLVER_GUROBILPSOLVER
 #define STORM_SOLVER_GUROBILPSOLVER
 
+#include <map>
 #include "src/solver/LpSolver.h"
 #include "src/exceptions/NotImplementedException.h"
 
diff --git a/src/solver/LpSolver.cpp b/src/solver/LpSolver.cpp
new file mode 100644
index 000000000..29840ac85
--- /dev/null
+++ b/src/solver/LpSolver.cpp
@@ -0,0 +1,23 @@
+
+#include "LpSolver.h"
+
+#include "src/storage/expressions/Expression.h"
+#include "src/storage/expressions/ExpressionManager.h"
+
+
+
+namespace storm {
+    namespace solver {
+        LpSolver::LpSolver() : manager(new storm::expressions::ExpressionManager()), currentModelHasBeenOptimized(false), modelSense(ModelSense::Minimize) {
+            // Intentionally left empty.
+        }
+        
+        LpSolver::LpSolver(ModelSense const& modelSense) : manager(new storm::expressions::ExpressionManager()), currentModelHasBeenOptimized(false), modelSense(modelSense) {
+            // Intentionally left empty.
+        }
+        
+        storm::expressions::Expression LpSolver::getConstant(double value) const {
+            return manager->rational(value);
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/solver/LpSolver.h b/src/solver/LpSolver.h
index 50a1be39e..2ea06af2c 100644
--- a/src/solver/LpSolver.h
+++ b/src/solver/LpSolver.h
@@ -4,11 +4,13 @@
 #include <string>
 #include <vector>
 #include <cstdint>
-
-#include "src/storage/expressions/Expression.h"
-#include "src/storage/expressions/ExpressionManager.h"
-
 namespace storm {
+    namespace expressions {
+        class ExpressionManager;
+        class Variable;
+        class Expression;
+    }
+    
     namespace solver {
         /*!
          * An interface that captures the functionality of an LP solver.
@@ -24,19 +26,14 @@ namespace storm {
             /*!
              * Creates an empty LP solver. By default the objective function is assumed to be minimized.
              */
-            LpSolver() : manager(new storm::expressions::ExpressionManager()), currentModelHasBeenOptimized(false), modelSense(ModelSense::Minimize) {
-                // Intentionally left empty.
-            }
-            
+            LpSolver();
             /*!
              * Creates an empty LP solver with the given model sense.
              *
              * @param modelSense A value indicating whether the objective function of this model is to be minimized or
              * maximized.
              */
-            LpSolver(ModelSense const& modelSense) : manager(new storm::expressions::ExpressionManager()), currentModelHasBeenOptimized(false), modelSense(modelSense) {
-                // Intentionally left empty.
-            }
+            LpSolver(ModelSense const& modelSense);
 
             /*!
              * Registers an upper- and lower-bounded continuous variable, i.e. a variable that may take all real values
@@ -139,9 +136,7 @@ namespace storm {
              * @param value The value of the constant.
              * @return The resulting expression.
              */
-            storm::expressions::Expression getConstant(double value) const {
-                return manager->rational(value);
-            }
+            storm::expressions::Expression getConstant(double value) const;
             
             /*!
              * Updates the model to make the variables that have been declared since the last call to <code>update</code>
diff --git a/src/solver/SymbolicGameSolver.h b/src/solver/SymbolicGameSolver.h
index ff5d64056..6abebee54 100644
--- a/src/solver/SymbolicGameSolver.h
+++ b/src/solver/SymbolicGameSolver.h
@@ -1,6 +1,8 @@
 #ifndef STORM_SOLVER_SYMBOLICGAMESOLVER_H_
 #define STORM_SOLVER_SYMBOLICGAMESOLVER_H_
 
+#include <set>
+#include <vector>
 #include "src/storage/expressions/Variable.h"
 
 #include "src/storage/dd/Bdd.h"
diff --git a/src/solver/SymbolicLinearEquationSolver.h b/src/solver/SymbolicLinearEquationSolver.h
index 6cd437673..7defb0b79 100644
--- a/src/solver/SymbolicLinearEquationSolver.h
+++ b/src/solver/SymbolicLinearEquationSolver.h
@@ -3,6 +3,7 @@
 
 #include <memory>
 #include <set>
+#include <vector>
 #include <boost/variant.hpp>
 
 #include "src/storage/expressions/Variable.h"
diff --git a/src/solver/Z3SmtSolver.cpp b/src/solver/Z3SmtSolver.cpp
index 082ab3c28..fed950c2a 100644
--- a/src/solver/Z3SmtSolver.cpp
+++ b/src/solver/Z3SmtSolver.cpp
@@ -2,6 +2,7 @@
 #include "src/utility/macros.h"
 #include "src/exceptions/NotSupportedException.h"
 #include "src/exceptions/InvalidStateException.h"
+#include "src/exceptions/InvalidArgumentException.h"
 
 namespace storm {
 	namespace solver {
diff --git a/src/solver/Z3SmtSolver.h b/src/solver/Z3SmtSolver.h
index f00f67b89..00dc8d434 100644
--- a/src/solver/Z3SmtSolver.h
+++ b/src/solver/Z3SmtSolver.h
@@ -46,7 +46,7 @@ namespace storm {
 			virtual void reset() override;
 
 			virtual void add(storm::expressions::Expression const& assertion) override;
-
+              
 			virtual CheckResult check() override;
 
 			virtual CheckResult checkWithAssumptions(std::set<storm::expressions::Expression> const& assumptions) override;
@@ -57,7 +57,7 @@ namespace storm {
 
 			virtual storm::expressions::SimpleValuation getModelAsValuation() override;
             
-            virtual std::shared_ptr<SmtSolver::ModelReference> getModel() override;
+                        virtual std::shared_ptr<SmtSolver::ModelReference> getModel() override;
 
 			virtual std::vector<storm::expressions::SimpleValuation> allSat(std::vector<storm::expressions::Variable> const& important) override;
 
diff --git a/src/storage/dd/CuddDdForwardIterator.cpp b/src/storage/dd/CuddDdForwardIterator.cpp
index 07b0a7e59..170bb5f54 100644
--- a/src/storage/dd/CuddDdForwardIterator.cpp
+++ b/src/storage/dd/CuddDdForwardIterator.cpp
@@ -2,6 +2,7 @@
 #include "src/storage/dd/CuddDdManager.h"
 #include "src/storage/dd/DdMetaVariable.h"
 #include "src/utility/macros.h"
+#include "src/storage/expressions/ExpressionManager.h"
 
 namespace storm {
     namespace dd {
diff --git a/src/storage/dd/CuddDdManager.cpp b/src/storage/dd/CuddDdManager.cpp
index d7adf1a6c..d84f3e602 100644
--- a/src/storage/dd/CuddDdManager.cpp
+++ b/src/storage/dd/CuddDdManager.cpp
@@ -6,6 +6,7 @@
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidArgumentException.h"
 #include "src/settings/SettingsManager.h"
+#include "src/storage/expressions/ExpressionManager.h"
 
 namespace storm {
     namespace dd {
diff --git a/src/storage/dd/CuddDdManager.h b/src/storage/dd/CuddDdManager.h
index 522be1fba..5bf1c3080 100644
--- a/src/storage/dd/CuddDdManager.h
+++ b/src/storage/dd/CuddDdManager.h
@@ -6,13 +6,18 @@
 
 #include "src/storage/dd/DdManager.h"
 #include "src/storage/dd/CuddDdMetaVariable.h"
-#include "src/storage/expressions/ExpressionManager.h"
 #include "src/storage/expressions/Variable.h"
 #include "src/utility/OsDetection.h"
 
 // Include the C++-interface of CUDD.
 #include "cuddObj.hh"
 
+namespace storm {
+    namespace expressions {
+        class Variable;
+    }
+}
+
 namespace storm {
     namespace dd {
         template<>
diff --git a/src/storage/dd/CuddDdMetaVariable.h b/src/storage/dd/CuddDdMetaVariable.h
index 4f016a6ce..fea461229 100644
--- a/src/storage/dd/CuddDdMetaVariable.h
+++ b/src/storage/dd/CuddDdMetaVariable.h
@@ -11,7 +11,7 @@
 #include "src/storage/dd/CuddAdd.h"
 #include "src/storage/dd/DdMetaVariable.h"
 #include "src/storage/dd/CuddDdForwardIterator.h"
-#include "src/storage/expressions/Expression.h"
+
 
 namespace storm {
     namespace dd {
diff --git a/src/storage/expressions/BaseExpression.h b/src/storage/expressions/BaseExpression.h
index 0a853c1eb..f9b2792f4 100644
--- a/src/storage/expressions/BaseExpression.h
+++ b/src/storage/expressions/BaseExpression.h
@@ -8,18 +8,17 @@
 #include <iostream>
 
 #include "src/storage/expressions/Type.h"
-#include "src/storage/expressions/Valuation.h"
-#include "src/storage/expressions/ExpressionVisitor.h"
-#include "src/storage/expressions/OperatorType.h"
-#include "src/exceptions/InvalidArgumentException.h"
 #include "src/utility/OsDetection.h"
+#include <boost/any.hpp>
 
 namespace storm {
     namespace expressions {
         // Forward-declare expression manager.
         class ExpressionManager;
         class Variable;
-        
+        class Valuation;
+        class ExpressionVisitor;
+        enum struct OperatorType;
         /*!
          * The base class of all expression classes.
          */
diff --git a/src/storage/expressions/BinaryBooleanFunctionExpression.cpp b/src/storage/expressions/BinaryBooleanFunctionExpression.cpp
index 68a643329..6cb550609 100644
--- a/src/storage/expressions/BinaryBooleanFunctionExpression.cpp
+++ b/src/storage/expressions/BinaryBooleanFunctionExpression.cpp
@@ -1,6 +1,7 @@
 #include "src/storage/expressions/BinaryBooleanFunctionExpression.h"
 #include "src/storage/expressions/BooleanLiteralExpression.h"
 #include "src/storage/expressions/ExpressionManager.h"
+#include "src/storage/expressions/ExpressionVisitor.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidTypeException.h"
 
diff --git a/src/storage/expressions/BinaryNumericalFunctionExpression.cpp b/src/storage/expressions/BinaryNumericalFunctionExpression.cpp
index de02d793b..95a326de1 100644
--- a/src/storage/expressions/BinaryNumericalFunctionExpression.cpp
+++ b/src/storage/expressions/BinaryNumericalFunctionExpression.cpp
@@ -4,10 +4,12 @@
 #include "src/storage/expressions/BinaryNumericalFunctionExpression.h"
 #include "src/storage/expressions/IntegerLiteralExpression.h"
 #include "src/storage/expressions/DoubleLiteralExpression.h"
+#include "src/storage/expressions/ExpressionVisitor.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidTypeException.h"
 #include "src/exceptions/InvalidStateException.h"
 
+
 namespace storm {
     namespace expressions {
         BinaryNumericalFunctionExpression::BinaryNumericalFunctionExpression(ExpressionManager const& manager, Type const& type, std::shared_ptr<BaseExpression const> const& firstOperand, std::shared_ptr<BaseExpression const> const& secondOperand, OperatorType operatorType) : BinaryExpression(manager, type, firstOperand, secondOperand), operatorType(operatorType) {
diff --git a/src/storage/expressions/BinaryRelationExpression.cpp b/src/storage/expressions/BinaryRelationExpression.cpp
index e6022380e..858536d0c 100644
--- a/src/storage/expressions/BinaryRelationExpression.cpp
+++ b/src/storage/expressions/BinaryRelationExpression.cpp
@@ -5,6 +5,7 @@
 #include "src/storage/expressions/BooleanLiteralExpression.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidTypeException.h"
+#include "src/storage/expressions/ExpressionVisitor.h"
 
 namespace storm {
     namespace expressions {
diff --git a/src/storage/expressions/BooleanLiteralExpression.cpp b/src/storage/expressions/BooleanLiteralExpression.cpp
index 9847e4bb3..9e4986b04 100644
--- a/src/storage/expressions/BooleanLiteralExpression.cpp
+++ b/src/storage/expressions/BooleanLiteralExpression.cpp
@@ -1,5 +1,6 @@
 #include "src/storage/expressions/BooleanLiteralExpression.h"
 #include "src/storage/expressions/ExpressionManager.h"
+#include "src/storage/expressions/ExpressionVisitor.h"
 
 namespace storm {
     namespace expressions {
diff --git a/src/storage/expressions/DoubleLiteralExpression.cpp b/src/storage/expressions/DoubleLiteralExpression.cpp
index be878f0b2..cab9fc31b 100644
--- a/src/storage/expressions/DoubleLiteralExpression.cpp
+++ b/src/storage/expressions/DoubleLiteralExpression.cpp
@@ -1,5 +1,6 @@
 #include "src/storage/expressions/DoubleLiteralExpression.h"
 #include "src/storage/expressions/ExpressionManager.h"
+#include "src/storage/expressions/ExpressionVisitor.h"
 
 namespace storm {
     namespace expressions {
diff --git a/src/storage/expressions/Expression.cpp b/src/storage/expressions/Expression.cpp
index 630e17a8a..ec723eedf 100644
--- a/src/storage/expressions/Expression.cpp
+++ b/src/storage/expressions/Expression.cpp
@@ -7,6 +7,7 @@
 #include "src/storage/expressions/LinearityCheckVisitor.h"
 #include "src/storage/expressions/Expressions.h"
 #include "src/exceptions/InvalidTypeException.h"
+#include "src/exceptions/InvalidArgumentException.h"
 #include "src/utility/macros.h"
 
 namespace storm {
diff --git a/src/storage/expressions/Expression.h b/src/storage/expressions/Expression.h
index afc04bf56..285a508b2 100644
--- a/src/storage/expressions/Expression.h
+++ b/src/storage/expressions/Expression.h
@@ -5,9 +5,7 @@
 #include <map>
 #include <unordered_map>
 
-#include "src/storage/expressions/SimpleValuation.h"
 #include "src/storage/expressions/BaseExpression.h"
-#include "src/storage/expressions/ExpressionVisitor.h"
 #include "src/utility/OsDetection.h"
 
 namespace storm {
@@ -15,6 +13,7 @@ namespace storm {
         // Foward-declare expression manager class.
         class ExpressionManager;
         class Variable;
+        class ExpressionVisitor;
         
         class Expression {
         public:
@@ -71,18 +70,18 @@ namespace storm {
              * @return An expression in which all identifiers in the key set of the mapping are replaced by the
              * expression they are mapped to.
              */
-			Expression substitute(std::map<Variable, Expression> const& variableToExpressionMap) const;
+            Expression substitute(std::map<Variable, Expression> const& variableToExpressionMap) const;
 
-			/*!
-			* Substitutes all occurrences of the variables according to the given map. Note that this substitution is
-			* done simultaneously, i.e., variables appearing in the expressions that were "plugged in" are not
-			* substituted.
-			*
-			* @param variableToExpressionMap A mapping from variables to the expression they are substituted with.
-			* @return An expression in which all identifiers in the key set of the mapping are replaced by the
-			* expression they are mapped to.
-			*/
-			Expression substitute(std::unordered_map<Variable, Expression> const& variableToExpressionMap) const;
+            /*!
+            * Substitutes all occurrences of the variables according to the given map. Note that this substitution is
+            * done simultaneously, i.e., variables appearing in the expressions that were "plugged in" are not
+            * substituted.
+            *
+            * @param variableToExpressionMap A mapping from variables to the expression they are substituted with.
+            * @return An expression in which all identifiers in the key set of the mapping are replaced by the
+            * expression they are mapped to.
+            */
+            Expression substitute(std::unordered_map<Variable, Expression> const& variableToExpressionMap) const;
             
             /*!
              * Evaluates the expression under the valuation of variables given by the valuation and returns the
diff --git a/src/storage/expressions/ExpressionManager.cpp b/src/storage/expressions/ExpressionManager.cpp
index 2685c940c..55ef846ed 100644
--- a/src/storage/expressions/ExpressionManager.cpp
+++ b/src/storage/expressions/ExpressionManager.cpp
@@ -4,6 +4,7 @@
 #include "src/storage/expressions/Variable.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidStateException.h"
+#include "src/exceptions/InvalidArgumentException.h"
 
 namespace storm {
     namespace expressions {
diff --git a/src/storage/expressions/IfThenElseExpression.cpp b/src/storage/expressions/IfThenElseExpression.cpp
index 4692675bf..adde41a2d 100644
--- a/src/storage/expressions/IfThenElseExpression.cpp
+++ b/src/storage/expressions/IfThenElseExpression.cpp
@@ -1,6 +1,7 @@
 #include "src/storage/expressions/IfThenElseExpression.h"
 
 #include "src/utility/macros.h"
+#include "ExpressionVisitor.h"
 #include "src/exceptions/InvalidAccessException.h"
 
 namespace storm {
diff --git a/src/storage/expressions/IntegerLiteralExpression.cpp b/src/storage/expressions/IntegerLiteralExpression.cpp
index f1050f70a..35ae07ee7 100644
--- a/src/storage/expressions/IntegerLiteralExpression.cpp
+++ b/src/storage/expressions/IntegerLiteralExpression.cpp
@@ -1,4 +1,6 @@
 #include "src/storage/expressions/IntegerLiteralExpression.h"
+
+#include "ExpressionVisitor.h"
 #include "src/storage/expressions/ExpressionManager.h"
 
 namespace storm {
diff --git a/src/storage/expressions/LinearCoefficientVisitor.cpp b/src/storage/expressions/LinearCoefficientVisitor.cpp
index ee7d397ae..8d7f39278 100644
--- a/src/storage/expressions/LinearCoefficientVisitor.cpp
+++ b/src/storage/expressions/LinearCoefficientVisitor.cpp
@@ -1,6 +1,7 @@
 #include "src/storage/expressions/LinearCoefficientVisitor.h"
 
 #include "src/storage/expressions/Expressions.h"
+
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidArgumentException.h"
 
diff --git a/src/storage/expressions/ToRationalFunctionVisitor.cpp b/src/storage/expressions/ToRationalFunctionVisitor.cpp
index 55840c301..5740cc66d 100644
--- a/src/storage/expressions/ToRationalFunctionVisitor.cpp
+++ b/src/storage/expressions/ToRationalFunctionVisitor.cpp
@@ -3,6 +3,7 @@
 #include <sstream>
 
 #include "src/utility/macros.h"
+#include "src/exceptions/InvalidArgumentException.h"
 
 #ifdef STORM_HAVE_CARL
 
diff --git a/src/storage/expressions/UnaryBooleanFunctionExpression.cpp b/src/storage/expressions/UnaryBooleanFunctionExpression.cpp
index 020d2de27..7c45e081d 100644
--- a/src/storage/expressions/UnaryBooleanFunctionExpression.cpp
+++ b/src/storage/expressions/UnaryBooleanFunctionExpression.cpp
@@ -1,5 +1,6 @@
 #include "src/storage/expressions/UnaryBooleanFunctionExpression.h"
 #include "src/storage/expressions/BooleanLiteralExpression.h"
+#include "ExpressionVisitor.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidTypeException.h"
 
diff --git a/src/storage/expressions/UnaryNumericalFunctionExpression.cpp b/src/storage/expressions/UnaryNumericalFunctionExpression.cpp
index e0181e139..987b5b5e1 100644
--- a/src/storage/expressions/UnaryNumericalFunctionExpression.cpp
+++ b/src/storage/expressions/UnaryNumericalFunctionExpression.cpp
@@ -5,6 +5,7 @@
 #include "src/storage/expressions/UnaryNumericalFunctionExpression.h"
 #include "src/storage/expressions/IntegerLiteralExpression.h"
 #include "src/storage/expressions/DoubleLiteralExpression.h"
+#include "ExpressionVisitor.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidTypeException.h"
 
diff --git a/src/storage/expressions/Variable.cpp b/src/storage/expressions/Variable.cpp
index 64c7174ca..aeb432f2a 100644
--- a/src/storage/expressions/Variable.cpp
+++ b/src/storage/expressions/Variable.cpp
@@ -1,5 +1,6 @@
 #include "src/storage/expressions/Variable.h"
 #include "src/storage/expressions/ExpressionManager.h"
+#include <cassert>
 
 namespace storm {
     namespace expressions {
@@ -40,6 +41,7 @@ namespace storm {
         }
         
         ExpressionManager const& Variable::getManager() const {
+            assert(manager != nullptr);
             return *manager;
         }
 
diff --git a/src/storage/expressions/Variable.h b/src/storage/expressions/Variable.h
index f3a271760..3ade039ed 100644
--- a/src/storage/expressions/Variable.h
+++ b/src/storage/expressions/Variable.h
@@ -3,14 +3,15 @@
 
 #include <cstdint>
 #include <memory>
+#include <functional>
 
 #include "src/utility/OsDetection.h"
-#include "src/storage/expressions/Type.h"
-#include "src/storage/expressions/Expression.h"
 
 namespace storm {
     namespace expressions {
         class ExpressionManager;
+        class Expression;
+        class Type;
         
         // This class captures a simple variable.
         class Variable {
diff --git a/src/storage/expressions/VariableExpression.cpp b/src/storage/expressions/VariableExpression.cpp
index 93c693515..8ac6cb8b2 100644
--- a/src/storage/expressions/VariableExpression.cpp
+++ b/src/storage/expressions/VariableExpression.cpp
@@ -1,4 +1,6 @@
 #include "src/storage/expressions/VariableExpression.h"
+#include "Valuation.h"
+#include "ExpressionVisitor.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidTypeException.h"
 
diff --git a/src/storage/prism/InitialConstruct.cpp b/src/storage/prism/InitialConstruct.cpp
index 9fff50a97..3c954120e 100644
--- a/src/storage/prism/InitialConstruct.cpp
+++ b/src/storage/prism/InitialConstruct.cpp
@@ -1,4 +1,5 @@
 #include "src/storage/prism/InitialConstruct.h"
+#include "src/storage/expressions/Variable.h"
 
 namespace storm {
     namespace prism {
diff --git a/src/storage/prism/InitialConstruct.h b/src/storage/prism/InitialConstruct.h
index 1bfd54d5f..5200fe805 100644
--- a/src/storage/prism/InitialConstruct.h
+++ b/src/storage/prism/InitialConstruct.h
@@ -2,12 +2,21 @@
 #define STORM_STORAGE_PRISM_INITIALCONSTRUCT_H_
 
 #include <string>
+#include <map>
 
 #include "src/storage/prism/LocatedInformation.h"
 #include "src/storage/expressions/Expression.h"
-#include "src/storage/expressions/Variable.h"
 #include "src/utility/OsDetection.h"
 
+
+namespace storm {
+        namespace expressions {
+            class Variable;
+        }
+}
+
+
+
 namespace storm {
     namespace prism {
         class InitialConstruct : public LocatedInformation {
diff --git a/src/storage/prism/Label.cpp b/src/storage/prism/Label.cpp
index dbc9d7f6f..977856dae 100644
--- a/src/storage/prism/Label.cpp
+++ b/src/storage/prism/Label.cpp
@@ -1,4 +1,5 @@
 #include "src/storage/prism/Label.h"
+#include "src/storage/expressions/Variable.h"
 
 namespace storm {
     namespace prism {
diff --git a/src/storage/prism/Label.h b/src/storage/prism/Label.h
index c0202cc04..82e10b26b 100644
--- a/src/storage/prism/Label.h
+++ b/src/storage/prism/Label.h
@@ -5,9 +5,16 @@
 
 #include "src/storage/prism/LocatedInformation.h"
 #include "src/storage/expressions/Expression.h"
-#include "src/storage/expressions/Variable.h"
 #include "src/utility/OsDetection.h"
 
+namespace storm {
+    namespace storage {
+        namespace expressions {
+            class Variable;
+        }
+    }
+}
+
 namespace storm {
     namespace prism {
         class Label : public LocatedInformation {
diff --git a/src/storage/prism/Module.h b/src/storage/prism/Module.h
index 421f4b6e1..48d252576 100644
--- a/src/storage/prism/Module.h
+++ b/src/storage/prism/Module.h
@@ -11,7 +11,6 @@
 #include "src/storage/prism/BooleanVariable.h"
 #include "src/storage/prism/IntegerVariable.h"
 #include "src/storage/prism/Command.h"
-#include "src/storage/expressions/VariableExpression.h"
 #include "src/utility/OsDetection.h"
 
 namespace storm {
diff --git a/src/storage/prism/Program.h b/src/storage/prism/Program.h
index 6a124e4e0..3d0d745b7 100644
--- a/src/storage/prism/Program.h
+++ b/src/storage/prism/Program.h
@@ -6,7 +6,6 @@
 #include <set>
 #include <boost/container/flat_set.hpp>
 
-#include "src/storage/expressions/Expression.h"
 #include "src/storage/prism/Constant.h"
 #include "src/storage/prism/Formula.h"
 #include "src/storage/prism/Label.h"
diff --git a/src/storage/prism/StateReward.cpp b/src/storage/prism/StateReward.cpp
index adcc423ec..8310f82bc 100644
--- a/src/storage/prism/StateReward.cpp
+++ b/src/storage/prism/StateReward.cpp
@@ -1,4 +1,5 @@
 #include "src/storage/prism/StateReward.h"
+#include "src/storage/expressions/Variable.h"
 
 namespace storm {
     namespace prism {
diff --git a/src/storage/prism/StateReward.h b/src/storage/prism/StateReward.h
index 535999faf..105d9267c 100644
--- a/src/storage/prism/StateReward.h
+++ b/src/storage/prism/StateReward.h
@@ -5,9 +5,17 @@
 
 #include "src/storage/prism/LocatedInformation.h"
 #include "src/storage/expressions/Expression.h"
-#include "src/storage/expressions/Variable.h"
 #include "src/utility/OsDetection.h"
 
+namespace storm {
+    namespace storage {
+        namespace expressions {
+            class Variable;
+        }
+    }
+}
+
+
 namespace storm {
     namespace prism {
         class StateReward : public LocatedInformation {
diff --git a/src/storage/prism/TransitionReward.cpp b/src/storage/prism/TransitionReward.cpp
index 182fe43a1..aadaf7a90 100644
--- a/src/storage/prism/TransitionReward.cpp
+++ b/src/storage/prism/TransitionReward.cpp
@@ -1,4 +1,5 @@
 #include "src/storage/prism/TransitionReward.h"
+#include "src/storage/expressions/Variable.h"
 
 namespace storm {
     namespace prism {
diff --git a/src/storage/prism/TransitionReward.h b/src/storage/prism/TransitionReward.h
index 4d693b899..8ace7c71c 100644
--- a/src/storage/prism/TransitionReward.h
+++ b/src/storage/prism/TransitionReward.h
@@ -5,9 +5,18 @@
 
 #include "src/storage/prism/LocatedInformation.h"
 #include "src/storage/expressions/Expression.h"
-#include "src/storage/expressions/Variable.h"
 #include "src/utility/OsDetection.h"
 
+
+namespace storm {
+    namespace storage {
+        namespace expressions {
+            class Variable;
+        }
+    }
+}
+
+
 namespace storm {
     namespace prism {
         class TransitionReward : public LocatedInformation {
diff --git a/src/utility/prism.cpp b/src/utility/prism.cpp
index 72c3c3258..b392616fe 100644
--- a/src/utility/prism.cpp
+++ b/src/utility/prism.cpp
@@ -1,4 +1,7 @@
 #include "src/utility/prism.h"
+#include "src/storage/expressions/ExpressionManager.h"
+#include "src/storage/prism/Program.h"
+
 
 namespace storm {
     namespace utility {
diff --git a/src/utility/prism.h b/src/utility/prism.h
index ea6057a15..87365e38d 100644
--- a/src/utility/prism.h
+++ b/src/utility/prism.h
@@ -2,15 +2,25 @@
 #define STORM_UTILITY_PRISM_H_
 
 #include <memory>
+#include <map>
 #include <boost/algorithm/string.hpp>
+#include <boost/container/flat_set.hpp>
 
-#include "src/storage/expressions/ExpressionManager.h"
-#include "src/storage/prism/Program.h"
 #include "src/utility/OsDetection.h"
 #include "src/utility/macros.h"
 #include "src/exceptions/InvalidArgumentException.h"
 
+
 namespace storm {
+    namespace expressions {
+        class Variable;
+        class Expression;
+    }
+    
+    namespace prism {
+        class Program;
+    }
+    
     namespace utility {
         namespace prism {
             // A structure holding information about a particular choice.
diff --git a/test/functional/adapter/Z3ExpressionAdapterTest.cpp b/test/functional/adapter/Z3ExpressionAdapterTest.cpp
index 763ffa3ef..4b220861b 100644
--- a/test/functional/adapter/Z3ExpressionAdapterTest.cpp
+++ b/test/functional/adapter/Z3ExpressionAdapterTest.cpp
@@ -148,7 +148,6 @@ TEST(Z3ExpressionAdapter, StormToZ3FloorCeil) {
 
 TEST(Z3ExpressionAdapter, Z3ToStormBasic) {
 	z3::context ctx;
-	unsigned args = 2;
 
     std::shared_ptr<storm::expressions::ExpressionManager> manager(new storm::expressions::ExpressionManager());
     manager->declareBooleanVariable("x");
diff --git a/test/functional/builder/die.pm b/test/functional/builder/die.pm
index af0797cff..6fd3f8231 100644
--- a/test/functional/builder/die.pm
+++ b/test/functional/builder/die.pm
@@ -29,4 +29,4 @@ label "three" = s=7&d=3;
 label "four" = s=7&d=4;
 label "five" = s=7&d=5;
 label "six" = s=7&d=6;
-label "done" = s=7;
+label "done" = s=7;
\ No newline at end of file
diff --git a/test/functional/solver/GlpkLpSolverTest.cpp b/test/functional/solver/GlpkLpSolverTest.cpp
index 5aeb01dc7..3c0112cf7 100644
--- a/test/functional/solver/GlpkLpSolverTest.cpp
+++ b/test/functional/solver/GlpkLpSolverTest.cpp
@@ -2,11 +2,14 @@
 #include "storm-config.h"
 
 #ifdef STORM_HAVE_GLPK
+#include "src/storage/expressions/Variable.h"
 #include "src/solver/GlpkLpSolver.h"
 #include "src/exceptions/InvalidStateException.h"
 #include "src/exceptions/InvalidAccessException.h"
 #include "src/settings/SettingsManager.h"
 
+#include "src/storage/expressions/Expressions.h"
+
 TEST(GlpkLpSolver, LPOptimizeMax) {
     storm::solver::GlpkLpSolver solver(storm::solver::LpSolver::ModelSense::Maximize);
     storm::expressions::Variable x;
diff --git a/test/functional/solver/GurobiLpSolverTest.cpp b/test/functional/solver/GurobiLpSolverTest.cpp
index 6c07a1f19..7e1547333 100644
--- a/test/functional/solver/GurobiLpSolverTest.cpp
+++ b/test/functional/solver/GurobiLpSolverTest.cpp
@@ -6,6 +6,8 @@
 #include "src/exceptions/InvalidStateException.h"
 #include "src/exceptions/InvalidAccessException.h"
 #include "src/settings/SettingsManager.h"
+#include "src/storage/expressions/Variable.h"
+#include "src/storage/expressions/Expressions.h"
 
 TEST(GurobiLpSolver, LPOptimizeMax) {
     storm::solver::GurobiLpSolver solver(storm::solver::LpSolver::ModelSense::Maximize);
diff --git a/test/functional/solver/Z3SmtSolverTest.cpp b/test/functional/solver/Z3SmtSolverTest.cpp
index 4e2b1b63c..7030777be 100644
--- a/test/functional/solver/Z3SmtSolverTest.cpp
+++ b/test/functional/solver/Z3SmtSolverTest.cpp
@@ -162,7 +162,6 @@ TEST(Z3SmtSolver, AllSat) {
     std::shared_ptr<storm::expressions::ExpressionManager> manager(new storm::expressions::ExpressionManager());
     
     storm::solver::Z3SmtSolver s(*manager);
-    storm::solver::SmtSolver::CheckResult result = storm::solver::SmtSolver::CheckResult::Unknown;
     
     storm::expressions::Variable a = manager->declareIntegerVariable("a");
     storm::expressions::Variable b = manager->declareIntegerVariable("b");
diff --git a/test/functional/storm-functional-tests.cpp b/test/functional/storm-functional-tests.cpp
index 30709a39d..5051bb659 100644
--- a/test/functional/storm-functional-tests.cpp
+++ b/test/functional/storm-functional-tests.cpp
@@ -8,6 +8,7 @@
 #include "log4cplus/consoleappender.h"
 #include "log4cplus/fileappender.h"
 
+#include "storm-config.h"
 #include "src/settings/SettingsManager.h"
 
 log4cplus::Logger logger;