diff --git a/include/plasp/pddl/Requirement.h b/include/plasp/pddl/Requirement.h
index b0831ea..159c1ae 100644
--- a/include/plasp/pddl/Requirement.h
+++ b/include/plasp/pddl/Requirement.h
@@ -1,6 +1,8 @@
 #ifndef __PLASP__PDDL__REQUIREMENT_H
 #define __PLASP__PDDL__REQUIREMENT_H
 
+#include <plasp/utils/Parser.h>
+
 namespace plasp
 {
 namespace pddl
@@ -12,28 +14,36 @@ namespace pddl
 //
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
-enum class Requirement
+struct Requirement
 {
-	STRIPS,
-	Typing,
-	NegativePreconditions,
-	DisjunctivePreconditions,
-	Equality,
-	ExistentialPreconditions,
-	UniversalPreconditions,
-	QuantifiedPreconditions,
-	ConditionalEffects,
-	Fluents,
-	NumericFluents,
-	ADL,
-	DurativeActions,
-	DurationInequalities,
-	ContinuousEffects,
-	DerivedPredicates,
-	TimedInitialLiterals,
-	Preferences,
-	Constraints,
-	ActionCosts
+	enum class Type
+	{
+		STRIPS,
+		Typing,
+		NegativePreconditions,
+		DisjunctivePreconditions,
+		Equality,
+		ExistentialPreconditions,
+		UniversalPreconditions,
+		QuantifiedPreconditions,
+		ConditionalEffects,
+		Fluents,
+		NumericFluents,
+		ADL,
+		DurativeActions,
+		DurationInequalities,
+		ContinuousEffects,
+		DerivedPredicates,
+		TimedInitialLiterals,
+		Preferences,
+		Constraints,
+		ActionCosts
+	};
+
+	static Requirement::Type fromPDDL(utils::Parser &parser);
+
+	static void toPDDL(std::ostream &ostream, Requirement::Type requirementType);
+	static void toASP(std::ostream &ostream, Requirement::Type requirementType);
 };
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
diff --git a/src/plasp/pddl/Requirement.cpp b/src/plasp/pddl/Requirement.cpp
new file mode 100644
index 0000000..ec8c168
--- /dev/null
+++ b/src/plasp/pddl/Requirement.cpp
@@ -0,0 +1,110 @@
+#include <plasp/pddl/Requirement.h>
+
+#include <boost/assert.hpp>
+#include <boost/assign.hpp>
+#include <boost/bimap.hpp>
+
+#include <plasp/pddl/Identifier.h>
+#include <plasp/utils/ParserException.h>
+
+namespace plasp
+{
+namespace pddl
+{
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+//
+// Requirement
+//
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+using RequirementTypeNames = boost::bimap<Requirement::Type, const char *>;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+const RequirementTypeNames requirementTypesToPDDL = boost::assign::list_of<RequirementTypeNames::relation>
+	(Requirement::Type::STRIPS, "strips")
+	(Requirement::Type::Typing, "typing")
+	(Requirement::Type::NegativePreconditions, "negative-preconditions")
+	(Requirement::Type::DisjunctivePreconditions, "disjunctive-preconditions")
+	(Requirement::Type::Equality, "equality")
+	(Requirement::Type::ExistentialPreconditions, "existential-preconditions")
+	(Requirement::Type::UniversalPreconditions, "universal-preconditions")
+	(Requirement::Type::QuantifiedPreconditions, "quantified-preconditions")
+	(Requirement::Type::ConditionalEffects, "conditional-effects")
+	(Requirement::Type::Fluents, "fluents")
+	(Requirement::Type::NumericFluents, "numeric-fluents")
+	(Requirement::Type::ADL, "adl")
+	(Requirement::Type::DurativeActions, "durative-actions")
+	(Requirement::Type::DurationInequalities, "duration-inequalities")
+	(Requirement::Type::ContinuousEffects, "continuous-effects")
+	(Requirement::Type::DerivedPredicates, "derived-predicates")
+	(Requirement::Type::TimedInitialLiterals, "timed-initial-literals")
+	(Requirement::Type::Preferences, "preferences")
+	(Requirement::Type::Constraints, "constraints")
+	(Requirement::Type::ActionCosts, "action-costs");
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+const RequirementTypeNames requirementTypesToASP = boost::assign::list_of<RequirementTypeNames::relation>
+	(Requirement::Type::STRIPS, "strips")
+	(Requirement::Type::Typing, "typing")
+	(Requirement::Type::NegativePreconditions, "negativePreconditions")
+	(Requirement::Type::DisjunctivePreconditions, "disjunctivePreconditions")
+	(Requirement::Type::Equality, "equality")
+	(Requirement::Type::ExistentialPreconditions, "existentialPreconditions")
+	(Requirement::Type::UniversalPreconditions, "universalPreconditions")
+	(Requirement::Type::QuantifiedPreconditions, "quantifiedPreconditions")
+	(Requirement::Type::ConditionalEffects, "conditionalEffects")
+	(Requirement::Type::Fluents, "fluents")
+	(Requirement::Type::NumericFluents, "numericFluents")
+	(Requirement::Type::ADL, "adl")
+	(Requirement::Type::DurativeActions, "durativeActions")
+	(Requirement::Type::DurationInequalities, "durationInequalities")
+	(Requirement::Type::ContinuousEffects, "continuousEffects")
+	(Requirement::Type::DerivedPredicates, "derivedPredicates")
+	(Requirement::Type::TimedInitialLiterals, "timedInitialLiterals")
+	(Requirement::Type::Preferences, "preferences")
+	(Requirement::Type::Constraints, "constraints")
+	(Requirement::Type::ActionCosts, "actionCosts");
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+Requirement::Type Requirement::fromPDDL(utils::Parser &parser)
+{
+	const auto requirementName = parser.parseIdentifier(isIdentifier);
+
+	const auto match = requirementTypesToPDDL.right.find(requirementName.c_str());
+
+	if (match == requirementTypesToPDDL.right.end())
+		throw utils::ParserException(parser.row(), parser.column(), "Could not parse requirement");
+
+	return match->second;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+void Requirement::toPDDL(std::ostream &ostream, Requirement::Type requirementType)
+{
+	const auto match = requirementTypesToPDDL.left.find(requirementType);
+
+	BOOST_ASSERT(match != requirementTypesToPDDL.left.end());
+
+	ostream << match->second;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+void Requirement::toASP(std::ostream &ostream, Requirement::Type requirementType)
+{
+	const auto match = requirementTypesToASP.left.find(requirementType);
+
+	BOOST_ASSERT(match != requirementTypesToASP.left.end());
+
+	ostream << match->second;
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+}
+}