Within the United Nations (UN) system, a great number of specialized agencies, programmes and conventions are concerned with global environmental problems. The Council’s 1996 annual report (WBGU, 1997) describes in detail the scientifically focused international programmes and committees on global change, most of which were established by one or several UN specialized agencies and ICSU (International Council of Scientific Unions). These programmes and committees include the World Climate Research Programme (WCRP), the International Geosphere-Biosphere Programme (IGBP), the DIVERSITAS biosphere programme, the Intergovernmental Panel on Climate Change (IPCC), the International Human Dimensions of Global Environmental Change Programme (IHDP) and the UNESCO programme ‘Man and the Biosphere’ (MAB). The following overview presents the institutions within the UN system that are of particular relevance to the present report (Fig. B 4-1).