A technique of participatory mapping onto transparencies over aerial photographs - an aid to communication among non-literate people - was described in this paper. The technique was found to have resounding success when tested at two sites in Nepal covered by the Nepal-UK Community Forestry Project. Among a wide range of benefits, the photographs triggered discussion and fostered trust, because participants were convinced of the authenticity of the visual representations. Preliminary trials also suggested that surveying local forests using photographs in conjunction with GIS was more accurate and efficient than traditional compass-and-chain methods.