This thesis has been carried out with the Food and Agriculture Organisation (FAO) of the United Nations, who are in the process of developing a GIS-based andNo.8220Land and Water Information System for SomaliaandNo.8221. It is hoped that this thesis will provide some contribution to their work.br Water resources in Somalia must be understood in the most detail, and in the most practical manner, by the Somalis themselves. However, there has been only limited formal characterisation of those water resources, and as a result, this thesis is designed in part to provide a comprehensive overview of the surface water resources of Somalia, particularly the south of the country. This includes analysis of the basic characteristics of both rainfall and stream flowbr The focus of the thesis is on drought, which is an inescapable problem in a climate such as that of Somalia. Various aspects of drought must be considered, and further objectives could thus be outlined as follows:br andNo.8226To consider the problem of drought definition, and put this in the context of water availability in Southern Somaliabr andNo.8226To investigate the techniques available for drought analysis and apply these to Somaliabr andNo.8226To understand the influences on climatological and hydrological variability in Somalia, and thus the factors contributing to droughtbr Characteristics of rainfall and runoff will be considered independently. Similar techniques will be used for both, although some differences exist since rainfall is an intermittent process while the rivers in question are permanent. Analyses of the two water sources will then be compared in order to provide a more complete description.br