Thomas C. Duffy (born June 17, 1955) is Professor (adj) of Music in the School of Music and the Director of Bands at Yale University. He received his Bachelor of Science in Music Education (magna cum laude) and the first Master of Musical Arts in Composition from the University of Connecticut, and his Doctor of Musical Arts in Composition from Cornell University, where he studied with Karel Husa and Steven Stucky. He has taught music courses at the Hartford Conservatory, the University of Connecticut, the Auburn Maximum Security Correctional Facility, Cornell University, and Yale University. He was Associate Dean (1996-2000), the first Deputy Dean (2000-2005) and Acting Dean (2005-06) of the Yale School of Music.

Recordings and performances of Mr. Duffy's music include those by college bands, orchestras, and wind ensembles throughout the world. Mr. Duffy has conducted bands and orchestras throughout the United States and Japan, England, France, Ireland, Finland and Italy.

He has served as president of the New England College Band Association, president of the CBDNA (College Band Directors National Association) Eastern Division, president of Connecticut Composers Inc., publicity co-chairman for the World Association of Symphonic Bands and Ensembles, chairman of the Connecticut Music Educators Association Professional Affairs and Government Relations Committees, and a member of American Composers Alliance, BMI, and the American Bandmasters Association. Mr. Duffy is President-elect of the College Band Directors National Association, Music Editor of the American Composers Forum Bandquest Series, and a member of the Board of Directors of the New Haven Symphony Orchestra and Music Haven. He is a member of the Tanglewood II Planning Committee and was a member of the Tanglewood II Symposium in 2008. His music is published by American Composers Alliance, Ludwig Music and Bourne Company Music Publishers. Dr. Duffy was selected as Outstanding Music Educator of the Year by the Connecticut Music Educators Association (1996) and was awarded the Tercentennial Composition Medal (2001) and the Cultural Leadership Citation (2008) by the Yale School of Music. (May 2008)

In addition to composing music for world-class musicians and ensembles, Duffy has had a commitment to writing music for musicians at the beginning and middle stages of musical attainment, and is frequently commissioned by middle, high school and college bands. Recently he has pioneered a new genre of musical composition/ conducting - music that requires a bi-lateral conductor, that is, a conductor who can conduct different meters with each hand simultaneously (sharing downbeats). .