(1912-) South African civil-rights activist, one of the first full-time secretary-generals of the African National Congress (ANC), in 1964, with Nelson Mandela. He was imprisoned following the 1964 Rivonia Trial for opposition to the apartheid system and released, at the age of 77, as a gesture of reform by President F W de Klerk 1989. In 1991, when Mandela became ANC president, Sisulu became his deputy.