The ‘liberal hour’ of 1960s social reform is normally attributed to Labour party leadership (especially by Roy Jenkins) and to liberal Christian campaigning. This chapter challenges the latter, providing evidence for the key role of Humanists and atheists in leading campaigns for abortion law reform, homosexual law reforms, divorce law reform and euthanasia. It provides a general overview of the medical reform network amongst Humanists, plus three case studies: of Madeleine Simms’ attacks on the churches in the cause of abortion law reform; Eustace Chesser’s advocacy of widening sexual knowledge; and Harold Blackham’s inspirational leadership of campaigns for moral education to be added to the English school curriculum in religious education. What emerges is a new understanding of the ideological foundations for secular reform of medical and moral law in Britain in the 1960s and 1970s.