An Approved Products (APL) is a list of products created by the customer for all of the potential suppliers that have been approved prior to the bidding process that meet a defined specification. In some instances this list is also referred to as a qualified products list. Several suppliers will need the flexibility of multiple product lists to manage a complex and fast changing environment. For historical and audit trail purposes, groups may need to keep records of their approved product lists as they stood several years in the past.