The original Memorandum of Understanding was signed in 1983 by Secretaries of Agriculture and Interior and the Governors of MT, WY, WA, ID. The Memorandum of Agreement reflects the need to have top level agency participation on the IGBC. The most recent Memorandum of Agreement was revised in December 2013.
IGBC membership currently includes U.S.D.A Forest Service, U.S.D.I. Fish and Wildlife Service, U.S.D.A. Bureau of Land Management, U.S.D.I. National Park Service, the state wildlife agencies of Montana, Idaho, Wyoming and Washington, the British Columbia Wildlife Branch, the Alberta Wildlife Branch, and Parks Canada.