After the National Park Service was created in 1916, several nonprofit organizations formed to support park programs and projects not covered by government funding. By 1936 cooperating associations were formally recognized by Congress, which passed laws enabling them to operate in national parks.

Today a cooperating association is best described as a nonprofit organization dedicated to supporting the education and preservation goals of the National Park Service. Cooperating associations accomplish this through bookstore sales, membership support, book and publication development, research funding and other educational activities. Western National Parks Association donates nearly $2 million annually to its national park affiliates.