The Allied Translator and Interpreter Section (ATIS), also known as the Allied Translator and Interpreter Service or Allied Translator and Intelligence Service, was a joint Australian/American World War II intelligence agency which served as a centralized allied intelligence unit for the translation of intercepted Japanese communications, interrogations and negotiations in the Pacific Theater of Operations between September 1942 and December 1945. During the last few months of operation ATIS primarily focused on investigation of Japanese war crimes. The section was officially disbanded on April 30, 1946.

Sidney Forrester Mashbir was a senior officer in the United States Army who was primarily involved in military intelligence. Born in New York, he served in the Arizona Army National Guard during the Mexican-American Border War. Mashbir then held several posts in intelligence positions, taking credit for catching the first German spy in the United States, before departing for on a four-year assignment as a language officer to Japan in 1920. He resigned from the army in 1923 in an attempt to execute his own master plan devised to extract intelligence from Japan in event of a war. His plan failed as a result of the Great Kantō earthquake in September 1923 and he was left bankrupt; he consequently returned to the US as an engineering businessman.