Community participation, ownership and cost sharing are key components of Tanzania's water policy, in common with the broad international consensus on water governance. However these policy goals are difficult to achieve, beset with paradoxes and their benefits may be overstated, both in terms of efficiency of resource management and equality of outcomes. This article draws on longitudinal ethnographic research of a village water supply in Tanzania to explore two issues: the contested nature of community ownership and the complex evolution of a 'community-owned' institution. The evidence from the Uchira Water Users Association leads us to question some of the simplistic assumptions made concerning the capacity of local communities to manage service delivery and to balance equity and sustainability principles. The limitations of 'bottom-up' and demand led approaches need to be recognised without discrediting their potential for challenging inequalities. The article concludes with a consideration of some of the tensions in community-driven development, which raises some important questions about the role of the State and external agencies in setting and enforcing equity criteria in community-managed initiatives.