Texas A&M University has many unique traditions, but the annual muster ceremony held on April 21 is among the most hallowed. No other gathering brings more former students together for a single event, marked by Aggies in more than four hundred locations worldwide. Aggies originally observed San Jacinto Day—the victory on April 21, 1836, by the Texans over Santa Anna—with club activities. During the WWII defense of Corregidor in Manila Bay the muster tradition gained broader significance. Surrounded, pounded by several quarter-ton shells a minute, and with little hope of relief that April of 1942, Gen. George F. Moore '08 thought of his alma mater and sought out a roster of all Aggies on Corregidor. News of the Aggie spirit in that dark hour electrified the nation. This book traces the evolution of Aggie Muster from its early roots to the modern-day observance. Through research and hundreds of interviews, John A. Adams, Jr. '73 has captured the essence and spirit of this honored Texas Aggie tradition.