1906-1914 – He was assistant U.S. attorney in New York state and legal officer in the Bureau of Insular Affairs.

         – A professor at Harvard law school, Frankfurter was also active during these years outside the academic world.

1930-1937 – Among his works are The Public and Its Government and The Commerce Clause under Marshall, Taney, and Waite.

1939 – Was an associate justice of the United States Supreme Court.