Privatisation of public infrastructure has been the mantra of many development agencies since the late 1980s. Water supply is no exception, and various forms of private sector participation (PSP) have been tried in the water and sanitation sector. This article examines the results of these experiments. It suggests that PSP has had mixed results and that in several important respects the private sector seems to be no more efficient in delivering services than the public sector. Despite growing evidence of failures and increasing public pressure against it, privatisation in water and sanitation is still alive, however. Increasingly, it is being repackaged in new forms such as that of public-private partnership.