For nearly 40 years, a clandestine operation, based in the heart of London, provided secret but crucial support for the struggle against apartheid in South Africa. Founded by Canon Collins of St Paul's Cathedral, the Inter- national Defence and Aid Fund (IDAF) outwitted every move of the South African security services (BOSS) while still managing to smuggle in more than a hundred million pounds to the victims and opponents of apartheid. For the first time, people involved with IDAF explain exactly how they managed to defy BOSS, and agents of BOSS reveal how they tried to infiltrate and discredit IDAF.