The 2004 Reauthorization Act included a provision requiring all school food authorities to implement a school food-safety program based on HAACP principles in every school building. USDA, the National Food Service Management Institute and SNA all have provided guidance, resources and training for operators. Implementing HAACP is not a one-time endeavor but rather an ongoing systematic program that needs to be updated and maintained every year.The food safety program begins with the "Process Approach" to HAACP, which groups menu items into three key categories according to how many times each item passes through the temperature danger zone, then assigns "critical control points" and limits to foods in each of the categories using what is called Standard Operating Procedures (SOP's).