In the coming decades the world will need to more than double its food and feed production, almost all of the increase being needed in developing countries. This has socioeconomic and biophysical implications. Traditional component and commodity research addresses overly narrow issues at too small a scale. Rural development needs an eco-regional approach that integrates biophysical and socioeconomic work on cropping systems, livestock, the environment, and natural resources. This book contains the papers, response papers and discussion report of a five-day seminar on eco-regional approaches. It assesses the state of the art of systems approaches applied to eco-regional problems, presenting and discussing a number of case studies. Future research needs are discussed, as well as ways to improve collaboration between research institutes. The seminar on which the book is based was organised on behalf of the Directorate General for International Cooperation of the Netherlands Ministry of Foreign Affairs by the Research Institute for Agrobiology and Soil Fertility (AB-DLO), the Wageningen Agricultural University (WAU), and the International Potato Centre (CIP). It was held at the International Service for National Agricultural Research (ISNAR), and was attended by participants from all CGIAR centres, among others.