This first CAPRi sourcebook is a fitting commemoration of the 15th anniversary of CAPRi. The sourcebook is based directly on the experiences and lessons of CAPRi research from around the world. Its content is based on sound underlying research, but the presentation is simple, straightforward, and accessible. The objective of the book is to build capacity of research and development organizations to recognize the importance and relevance of CAPRi concepts and to apply the lessons and methods from CAPRi research to their work with communities, policymakers, and other stakeholders. It is our hope that it will serve not only as a relevant and practical guide for development practitioners, trainers, and policymakers, but will also be used in universities and other institutions of higher learning.