Communal areas in South Africa invariably lack cadastre and other information needed for sustainable planning. Usually land ownership is unclear and only limited state capacity exists in providing basic services infrastructure. This paper describes community mapping as a participatory means to encourage development. The impact of community-based mapping is assessed and if participatory methodology can fulfil its well-known objectives. Reflections on two community-based mapping projects facilitated with residents show that in these circumstances, community-based mapping is effective in bringing about change. Flamingo Crescent is an urban informal settlement located in Lansdowne, Cape Town. Informal settlements such as these are high density and organic, making service delivery difficult due to the lack of space. Re-blocking is an in-situ method of upgrading an informal settlement so that basic service and access can be provided. The Goedverwacht Moravian Mission Station in the Western Cape has no internal cadastral boundaries and therefore the spatial framework is fuzzy and confusing. The objective of the study is to use a mapping technique that is economically viable, fast and at an accuracy determined by purpose rather than technical and legal requirements for formal land registration. Findings spotlight some of the advantages of community-based mapping during these projects by assessing their impact using critical outcomes of participation, empowerment and ownership.