In 1965 a group of Australian students set out in a hired bus to highlight racial discrimination against sections of the Aboriginal population. The Freedom Ride, as it became known, stirred up bitter controversy as it exposed racial tensions in Australia. The scenes on board the bus were captured by an Australian radio reporter but were not allowed to be aired until several years later. Phillip Knightley assesses how effective the Freedom Ride was as a force for change. Producer Emma Kingsley