FAST is an acronym for “Free and Secure Trade.” It is a bilateral initiative between the United States and Canada and the United States and Mexico that gives partnering importers expedited release at national borders when transportation is by truck. It is for qualifying commercial shipments through risk-management principles, supply-chain security, industry partnerships and advanced targeting.

Definition Source: http://www.yrc.com/homeland/homelandsecurity_customs_border_protection.html