The greatest potential for expanding agricultural land in most developing countries lies in the savannahs dominated by tropical acid and infertile soils. This publication contains the studies conducted in a Coordinated Research Project (CRP) involving ten Member States to develop integrated crop, soil, water and nutrient management practices to increase and sustain agricultural productivity of these soils in Africa and Latin America. The work covered a range of representative environments and cropping systems. Results showed how appropriate crop, soil, water and nutrient management improved soil fertility status, promoted better soil and water conservation and thereby increased crop productivity under local farming conditions. This publication highlights sound strategies and approaches, including the application of nuclear and related techniques needed to foster sustainable agricultural intensification in tropical regions while paving the way for future projects.