Fenwick Smith studied under Joseph Mariano at the Eastman School of Music, graduating from there in 1972. Shortly thereafter he became a member of the New England Woodwind Quintet and began a thirteen year membership with Boston Musica Viva. He became the assistant principal flutist of the Boston Symphony Orchestra in 1978, serving in that position until September 2006. During this time he was also principal flutist of the Boston Pops Orchestra. Smith has also been a member of the Boston Chamber Music Society since 1984, and since 1983 has given annual recitals at Jordan Hall.
Smith has a reputation for playing new works and has notably made numerous premiere recordings of works by composers like Copland, Foote, Gaubert, Ginastera, Koechlin, Dahl, Harbison, Cage, Pinkham, Erwin Schulhoff, Schuller, Schoenberg, Ned Rorem, and Reinecke. He is currently on the faculty of the New England Conservatory.