The Leaders Congress of the Maritime Aboriginal Peoples Council, is the supreme body of MAPC. Each Member Council which must be an Aboriginal Peoples Representative Body situated in the Atlantic Region of Canada, has the privilege to join MAPC. The duly elected Chief of a Member Council has a seat at the Leaders Congress, as long as his or her official tenure with his or her representative organization continues.

The Leaders Congress operates on a consensus basis. Subject matters must be either of regional, national or international significance to the Communities of Aboriginal Peoples, and usually fall into categories of “social, cultural and educational programs or services”, “economic development”, “Treaty and Aboriginal Rights”, and “International conventions, protocols, and agreements”.

The Leaders Congress also, hold sessions at different locations throughout the Maritimes on high level administrative, budget and appointment matters including two or more Leaders Congress sessions on specific topics appropriate to be raised and discussed at the Congress.

Usually at the end of a Leaders Congress, a Congress Bulletin or Press Release is provided, highlighting subjects and outcomes discussed.