The Prime Vendor Pilot was conducted as part of USDA's Business Process Re-engineering efforts to improve the administration and operation of the Food Distribution Program on Indian Reservations. Under this pilot, USDA partnered with the Department of Defense, which had an existing contract with commercial vendors and distributors.

FNS published “The WIC Vendor Management Study, 1998” in July 2001 which examined, in part, the extent to which retail grocers, defined as WIC “vendors” were violating program rules and regulations. The 1998 study is a follow-up to the “WIC Vendor Issues Study, 1991” published by FNS in May 1993.