Introduction: Opportunities and risks

It is a known fact that, world wide, there are more than 200 international water systems and that some 60 per cent of the global population resides within such systems. This has important implications for international security of these water systems and the people dependent on them. With this in mind, the United Nations University (UNU), within the framework of the environmentally sustainable development initiatives, has carried out various activities related to such international water systems as the Aral and Caspian seas; and the Ganges, Jordan, Danube, La Plata, and Nile rivers (Nakayama and Jansky 2001). This volume reflects the continuing efforts of the UNU in the field of international water systems. The shared river systems in Southern Africa are featured in this volume. The Southern African region is one of the ‘‘hottest’’ areas in terms of managing international water systems, because (a) there is a great disparity in the availability of water between the relatively ‘‘wet’’ northern part of the region and the ‘‘dry’’ southern part, (b) the first-ever transboundary transfer of water (between Lesotho and South Africa) has occurred within the region, (c) discussions have taken place in many international water systems about sharing of water resources among basin countries, and (d) some planned water-transfer schemes have been the subject of disputes, in both environmental and security contexts. The author once worked on the Zambezi River system in the Southern African region towards establishment of a basin-wide management