Peter Taaffe (born April 1942) is a British Marxist (Trotskyist) political activist and journalist. He was the general secretary of the Socialist Party of England and Wales from its founding until 2020 and was a member of the International Executive Committee of the Committee for a Workers' International (CWI). Taaffe was the founding editor of the Trotskyist Militant newspaper in 1964, and became known as a leading member of the entryist Militant group. Taaffe was expelled from the Labour Party in 1983, along with four other members of Militant's editorial board