This chapter reviews the climatic resources, surface water resources, groundwater development, and research needs of the continent of Africa for irrigation development. Because of the complexity of African rivers, and the important traditional agricultural systems they support, the "river basin" approach of many development agencies seems inappropriate. The intervening effects of terrain and vegetation mean that the hydrological regimes of the larger rivers only respond slowly to rainfall inputs. A review of African hydrological environments means discussion of some of the most unique and difficult hydrological monitoring problems of the world. While Africa contains some of the largest rivers, lakes, deltas and swamps of the world, paradoxically the availability of water per unit area is the lowest in the world. Information on hydrological surveys funded by the Food and Agriculture Organization (FAO) can be obtained through their annual bibliography--the FAO Current Documentation Series.