 Following his time with the newspaper, he moved to Chicago to work for the advertising agency J. Walter Thompson.In 1932 he relocated to New York to work for the advertising agency Benton & Bowles, but in 1942 rejoined J. Walter Thompson, at their New York office.O'Meara went on to act as the Chief of Planning for the Office of Strategic Services, as well as the head of the information department of the Office of Price Administration, during World War II.