This volume investigates the structural development and administrative organization of the American Expeditionary Forces during the First World War. The text serves as an official historical record compiled by the Department of the Army, utilizing primary source documentation, organizational charts, and official correspondence to detail how the United States military transitioned from a peacetime force to a mobilized overseas army. It provides a foundational framework for understanding the logistical and command-level complexities faced by the American military leadership between 1917 and 1919.

Historians and military researchers utilize this volume as a primary reference for understanding the bureaucratic and structural evolution of the U.S. Army during the Great War. The text is noted for its high degree of technical detail and its value as a foundational administrative record.