Mortimer Graves served as executive director of ACLS from 1953-1957, a period of transition for the organization that culminated in the move of its offices from Washington, D.C. to New York City. In the early 1940s, while serving as secretary of ACLS, Graves had a pivotal role in ACLS’s Intensive Language Program, a collaboration between ACLS and the Linguistic Society of America to produce course materials in foreign languages needed by the military. He secured the grant from the Rockefeller Foundation that established the program and went on to coordinate the development of the well-known Spoken Language Series. The series pioneered the use of audio tapes along with written material, emphasizing speech over writing, and is considered the first self-study language method. Spoken Language Series materials for Russian, German, Dutch, Spanish, Italian, Japanese, Chinese, Thai, and Burmese, among others, were distributed throughout the armed forces during World War II.