Throughout the 1930s, Clarence's time was devoted to working with existing birth control organizations, often holding overlapping executive positions. He was president and delegate-at-large of the Pennsylvania Birth Control Federation; state delegate, one of five vice-presidents, and member of the Executive Committee of the Board of the American Birth Control League; medical field director of Margaret Sanger's Birth Control Clinical Research Bureau, they both work on special project such as The Negro Project; and treasurer and member of the board of Robert Dickinson's National Committee on Maternal Health. By 1938, Clarence had left Philadelphia and the University of Pennsylvania. He purchased a house outside of Boston, Massachusetts, and funded eight field workers who were nurturing the beginnings of community-supported birth control clinics in Montana, Tennessee, Virginia, Florida, throughout the East Coast, and in the Midwest. During this decade, Clarence and his fieldworkers were responsible for helping to establish birth control clinics in 40 cities in 14 American states.