This article's purpose primarily is to review the scientific literature on the development of analytical methods for the identification of irradiated foods over the past decade. The main modalities currently being employed or developed (e.g. physical vs. chemical vs. biological) are introduced, and their advantages and disadvantages discussed. Radiation/free radical chemistry and electron spin resonance (ESR) spectroscopy are presented in the most depth. Some recent food irradiation/ESR research from the authors' laboratories is included. Finally, it is hoped that this review will shed some light on the current status and prospects for food irradiation practices world-wide.