Abstract In the food industry quality assurance (QA) systems such as GMP, HACCP, ISO and BRC, are applied for assuring food quality. However, it is still unknown to what extent these QA systems contribute to the realization of quality. Therefore, an instrument is required that measures the effectiveness of food quality systems. This article analyzes several QA systems, and discusses the development of a conceptual model that aims at developing an objective diagnostic instrument. Successive research can use this instrument to assess performance of food quality systems.