Understanding body size and shape information of military personnel is critical for the design and development of clothing and individual equipment, and especially personal protective equipment. Recently, the U.S. Army performed an Army wide anthropometric survey of the current U.S. Army population. The previous data set was collected in 1988. When the body dimensions from the ANSUR 1988 and ANSUR II 2012 datasets were compared, there were clear increases in weight and circumferences since1988 for both males and females, but no meaningful increases in heights. These increases in weight and circumferences have a significant impact on the development of sizing systems. The impact of these changes are as theoretically demonstrated here that legacy size charts, based on the ANSUR 1988 data, would not accommodate the current U.S. Army population. Based on previous sizing system methodologies, a customized process was developed focusing on the unique requirements of the military acquisition lifecycle and the requirements for PPE. This methodology was made up of three steps 1 investigate the design problems related to design concept and function of the item along with the interrelationship among the population anthropometrics, the fit of the item, and the target accommodation rate 2 develop a prototype and perform iterative testing, where each size of the prototype is developed and modified as the sizing system is completed and 3 produce final products related to sizing systems, including prototypes in all sizes that accommodate the target population, the sizing chart for the item, and the size tariff for the production of the item. This optimization process should result in high accommodation rates for a combined male and female population, with a reduced number of sizes.