Reports the results of a study initiated by the FSIS in January 1990 to determine how to implement the HACCP system into meat and poultry inspection operations. The goals of the HACCP evaluation are: to evaluate the pre-implementation stages of HACCP models in the volunteer plants; to evaluate the conformance of the model HACCP plans and the plant-specific HACCP models with the HACCP principles developed by the National Advisory Committee on Microbiological Criteria for Foods; to evaluate the functioning and effectiveness of the plant-specific HACCP models in the volunteer plants; to evaluate the functioning and effectiveness of a HACCP-based inspection system in the volunteer plants; and to evaluate the potential impact for nationwise implementation of a HACCP-based inspection system in meat and poultry plants.