This chapter provides an overall conclusion and summary of the volume with brief summaries of each chapter. Part I covered soil-forming processes on different continents, focusing on humid regions of Asia and equatorial Africa. Part II presented a comparative analysis of pedogenic acidification processes under different geologic and climatic conditions in humid Asia, where Ultisols predominate, and then provided a comparative analysis of Oxisols/Ferralsols in Cameroon. The analysis in this section suggested that differences in basic soil properties such as clay mineral composition was often accompanied by, or correlated with, different ecosystem processes under natural vegetation, which could be regarded as an "ecosystem strategy for resource (nutrients) acquisition." In Part III, we analyzed the ecological adaptation of traditional agricultural practices to environmental conditions such as climate and soils, to develop a scientific basis for low-input agriculture. These practices, which have proved to be sustainable for some period at least, should be utilized for developing agricultural systems that depend less heavily on external resource inputs. In Part IV, several trials for establishing "minimumloss" management practices in the tropics were described. In summary, the authors would like to again emphasize that the development of agricultural systems appropriate for use in the tropics needs to be based on the scientific understanding of applied ecological processes, as was outlined in Parts III and IV, in which the loss of soil resources can be minimized by controlling fluxes of carbon, nitrogen, and minerals. As was stated in the introduction, these efforts are justified both from an economic perspective related to the poverty of many of the farmers in tropical countries and the vulnerability of agricultural productivity in tropical countries to changing conditions such as climate change, soil degradation, and worldwide depletion of water and nutrient resources. Further studies on local ecosystem processes and agricultural practices should be encouraged from these perspectives.