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