The term regional county municipality or RCM (French: municipalité régionale de comté, MRC) is used in Quebec to refer to one of 87 county-like political entities. In some older English translations they were called county regional municipality.
Regional county municipalities are a supralocal type of regional municipality, and act as the local municipality in unorganized territories within their borders. The system of regional county municipalities was introduced beginning in 1979 to replace the historic counties of Quebec. In most cases, the territory of an RCM corresponds to that of a census division, however there are a few exceptions.
Some local municipalities are outside any regional county municipality (hors MRC). This includes some municipalities within urban agglomerations and also some aboriginal lands, such as Indian reserves that are enclaves within the territory of an RCM but not juridically part of it. Where complete territorial coverage is desired, for example for the census, the Indian reserve enclaves are added in to create "geographical RCMs", and the urban agglomerations are considered to be "territories equivalent to an RCM".
More information on the Wikipedia page .