diff --git a/docs/ReleaseNotes.md b/docs/ReleaseNotes.md
index 05396d88..1c430a90 100644
--- a/docs/ReleaseNotes.md
+++ b/docs/ReleaseNotes.md
@@ -6,6 +6,8 @@ Release 11.1.0
 
 ### Minor Updates
 
+- Added new property `hasFirstMember`. Issue [#549](https://github.com/semanticarts/gist/issues/549).
+
 ### Patch Updates
 
 - Improved the clarity and accuracy of annotations on serveral terms, including definitions, examples, and scope notes:
diff --git a/gistCore.ttl b/gistCore.ttl
index 102bf1ac..7fcb21a2 100644
--- a/gistCore.ttl
+++ b/gistCore.ttl
@@ -1712,6 +1712,20 @@ gist:OrderedCollection
 				owl:onProperty gist:hasMember ;
 				owl:allValuesFrom gist:OrderedMember ;
 			]
+			[
+				owl:unionOf (
+					[
+						a owl:Restriction ;
+						owl:onProperty gist:hasMember ;
+						owl:cardinality "0"^^xsd:nonNegativeInteger ;
+					]
+					[
+						a owl:Restriction ;
+						owl:onProperty gist:hasFirstMember ;
+						owl:someValuesFrom owl:Thing ;
+					]
+				) ;
+			]
 		) ;
 	] ;
 	skos:definition "A collection in which the members are sequentially ordered. All members of an OrderedCollection are OrderedMembers."^^xsd:string ;
@@ -3224,6 +3238,19 @@ gist:hasDirectSuperCategory
 	skos:scopeNote "Unlike its superproperty gist:hasSuperCategory, this property is not transitive. It is essentially the same as the non-transitive skos:broader, using gist:Category rather than skos:Concept."^^xsd:string ;
 	.
 
+gist:hasFirstMember
+	a
+		owl:ObjectProperty ,
+		owl:InverseFunctionalProperty
+		;
+	rdfs:subPropertyOf gist:hasMember ;
+	rdfs:domain gist:OrderedCollection ;
+	rdfs:range gist:OrderedMember ;
+	skos:definition "Relates an ordered collection to its first member."^^xsd:string ;
+	skos:prefLabel "has first member"^^xsd:string ;
+	skos:scopeNote "Given the Open World Assumption, the absence of a predecessor does not entail that an ordered member is the first member of an ordered collection. This property is used to explicitly indicate the first member. Since ordered collections may not be strictly ordered, there can be more than one first member."^^xsd:string ;
+	.
+
 gist:hasGiver
 	a owl:ObjectProperty ;
 	rdfs:subPropertyOf gist:hasParticipant ;