This paper describes a community enumeration and mapping programme in five low-income settlements in Dar es Salaam. The inhabitants documented their settlement and its problems in detail, especially for water and sanitation, with support from the UK charity, WaterAid, and PEVODE, a Tanzanian NGO. The paper describes the planning and implementation of the enumeration and mapping, the information gathered, and how it was used. It looks specifically on some of the issues relating to the privatisation of the public water utilities. It also describes the way in which the process helped establish links between these communities and government agencies, and stimulated local action to address some of the problems identified. The community proved an essential resource in the mapping process. The authors recommend that a more holistic approach should be considered to tackle all of the issues arising in the community, water and sanity can not be specifically isolated. The mapping exercise helped the community to feel empowered to demand support for dealing with issues relating to water and sanitation. The awareness of the privatisation of the water utilities was little, and the authors of this study recommend that organisations such as PEVODE should start an awareness-raising campaign in the community. The study also revealed that other parts (than that in focus for the study) of the city would be affected by the privatisation of the water.