Michael Stephen Portnoy (born April 20, 1967) is an American musician best known as the drummer, backing vocalist, and co-founder of the progressive metal band Dream Theater.
In September 2010, Portnoy announced his departure from Dream Theater after 25 years, with Mike Mangini succeeding him as the band’s drummer. In October 2023, 13 years after his departure, the band announced his return.
