Decentralisation of International Institute of Tropical Agriculture's (IITA) research activities advanced, with specialised centres now catering for the research needs of the Humid Forest, the Degraded Forest, the Forest-Savannah transition zone and the Southern Guinea Savannah (SGS), the Northern Guinea Savannah (NGS) and the Wet Mid-Altitude Zone. The goals of the Institute's resource and crop management research were reformulated during the 1995 External Program Review as: the promotion of the development of sustainable production systems for sub-humid and humid African agriculture through improved resource management, with special attention to problems of environmental degradation. IITA was designated as the CGIAR's lead institute for the Ecoregional Program for the Humid and Subhumid Tropics of sub-Saharan Africa (EPHTA), which was launched in 1996 and would cover two agro-ecological zones (AEZs): the Humid Forest and the Moist Savannah Zones. Eco-regions were delineated and the 'Forest Margins' Benchmark in Cameroon, a natural resource management (NRM) survey method, was combined with a rapid characterisation of soils and vegetation.