A comprehensive guide to the calibration, use, and maintenance of the alanine-EPR metrology system for high-dose radiation dosimetry is presented. Alanine dosimetry is the system of choice for calibration services for all major primary and secondary calibration laboratories worldwide. Over the past 50 years alanine dosimetry has been transformed from an art to a state-of-the-art technology that serves the metrology specialist as well as the industrial technician. This guide outlines the critical elements that must be addressed to operate an EPR measurement service at the highest levels of accuracy and precision. The nuances of EPR, the harsh environment of high-dose high energy radiation processing, and the complexities of free radical chemistry combine to present many challenges. The success of alanine-EPR metrology has led many to search for new EPR dosimeters, it is hoped that the information presented here may serve as a template for the development of new systems that will improve or expand current metrology services.