Military psychology is the application of the accumulated knowledge and methods of psychology to the many needs of the military. In the United States, the very first such application began following the nation's entry into World War I (WWI). Members of the nascent American Psychological Association under the direction of Robert Yerkes met to discuss ways the field of psychology could aid in the war effort. Primary among these was the task of recruit selection and determination of suitability for various military assignments. This involved developing the classification testing program of the U.S. Army including the U.S. Army Alpha and Beta tests (intelligence tests for literates and illiterates, respectively) used during WWI, followed by more advanced aptitude tests such as the Army [Page 389]General Classification ...