This is the ValueSet that contains all the codes in ActRelationshipJoinDetached (http://terminology.hl7.org/ValueSet/v3-ActRelationshipJoinDetached) and ActRelationshipJoinDetached (http://terminology.hl7.org/ValueSet/v3-ActRelationshipJoinDetached). E.g. what you have to deal with if you get resources containing codes in either of them