This is the CodeSystem that contains all the codes in ICPC2-ICD10 Thesaurus (English) (http://terminology.hl7.org/CodeSystem/icpc2-icd10-ENG) and ICPC2-ICD10 Thesaurus (English) (http://terminology.hl7.org/CodeSystem/icpc2-icd10-ENG). E.g. what you have to deal with if you get resources containing codes in either of them