In an increasingly complex and fast-paced world, organizations must develop strategies to enhance or optimize worker performance in order to achieve their goals. This is especially true, for example, in the military, where highly skilled and competent personnel are needed, and where, because of lengthy training requirements and financial constraints, getting the most out of its existing soldiers and civilian employees is critical to mission success. Therefore, in many ways the military serves as the best model to understand how humans, when required to go well beyond common capabilities, can optimally function in extreme circumstances. This chapter describes the origins of an Army study to investigate human performance optimization (HPO), the results of that initial study, and introduces the topics included in the current volume that speak to scientifically grounded strategies that may enable the Army and other organizations to optimize the cognitive, physical, and social aspects of employee performance. The topics included in this book are relevant to organizations and individuals that seek to remain competitive by achieving HPO.