In May 1939 about fifty psychologists attended a reunion in New York City to reminisce about their service in the First World War. Many prominent psychologists were on the guest list, including James Angell, Walter V. Bingham, Truman Kelley, Beardsley Ruml, Walter Dill Scott, Edward Thorndike, Leonard Thurstone, John B. Watson, and Robert Yerkes. They gathered to celebrate the twentieth anniversary of their demobilization as members of the Committee on Classification of Personnel, which had directed the army's personnel system during the war, and to congratulate their former commanding officer, Colonel Walter Dill Scott, who was retiring after two decades as president of Northwestern University.

The event was organized by Walter Bingham, the former executive secretary of the committee who was currently serving as president of the New York State Association for Applied Psychology. Bingham had been a vigorous proselytizer on behalf of applied psychology since the Great War. No doubt aware of the increasingly ominous political situation in Europe, he used the reunion to start rebuilding the military psychology network. One colleague had suggested that a military representative be invited so that “a new tie can be forged which will be the [start] of putting the services of some of the old crowd at the disposal of the country, should the emergency arise.” Bingham followed up, and the army sent a lieutenant colonel from the Adjutant General's Office to the gathering.