Retained austenite can be disastrous or increase the life of heat treated components. However, discussions on the right amount of retained austenite are only meaningful when measured correctly. The proper determination in microstructures samples requires a trained metallurgist and remains to be very subjective to the individual’s eye. Company standards of microstructure tables are used as individual solution. However, factual results are only achievable with the use of an X-ray diffractometer. This paper discusses the practical experience of metallurgical results and shows state of the art solutions as today’s standard.