This report presents the results of work in progress. It applies GIS techniques and newly available geo-referenced data to understand conditions underlying poverty and hunger in the world, with special reference to mountain environments and populations. Following the system developed by the United Nations Environment Programme – World Conservation Monitoring Centre (UNEP-WCMC) in 2000 for classifying mountain areas, hilly as well as high mountain areas are covered by the analysis. New data about global population density from the LandScan 2000 map has made it possible to estimate population figures for each mountain area class, as well as for other parameters about agricultural land use, farming systems, environmental constraints and yields per person that contribute to the estimation of the number of vulnerable rural mountain people. The report notes that, although vulnerable people represent a far greater proportion of the total population in high mountain areas, their absolute numbers are far greater at lower elevations. In all, around 245 million rural mountain people in developing and transition countries are estimated to be vulnerable to food insecurity. Of these, 87 percent live below 2 500 m where population pressure and increasing demand for grazing land are creating serious sustainability problems for mountain environments and the livelihood systems of the inhabitants. This report concludes with a brief summary of five areas of opportunity for developing more sustainable livelihood options for mountain people, namely, water, agriculture, conservation and tourism, forests and rangelands, and mountain industry and services.