The questions raised by government support for faith-based schools are now proving to be increasingly relevant and contentious. In one form or another they have a long history and are embedded in classical disagreements about the proper relationship between State and Church, or between secular power and religious freedom. They have been given a sharper edge by recent events, and by the emphasis laid by some governments on the importance of increasing public support for schools attached to different denominations and religions. Is it appropriate in a pluralist society to support some forms of religious expression and not others? What are the basic reasons for mingling (or indeed refusing to mingle) political and religious issues? What are the larger social effects of encouraging separate schooling for distinct sectors of society? These are among the questions raised and illuminated by this case study – historical and comparative in character – of the developing relationship between the State and the Catholic communities in three very different societies.