This is the CodeSystem that contains all the codes in ISO 4217 Currency code, HL7 use (http://terminology.hl7.org/CodeSystem/v3-iso4217-HL7) and ISO 4217 Currency code, HL7 use (http://terminology.hl7.org/CodeSystem/v3-iso4217-HL7). E.g. what you have to deal with if you get resources containing codes in either of them