Previously the role of social capital - defined as the institutions and networks of relationships between people, and the associated norms and values - in programs of poverty alleviation and development has risen to considerable prominence. Although development practitioners have long suspected that social capital does affect the efficiency and quality of most development processes, this book provides the rigorous empirical results needed to confirm that impression and translate it into effective and informed policymaking. It is based on a large volume of collected data, relying equally on quantitative and qualitative research methodologies to establish approaches for measuring social capital and its impact. The book documents the pervasive role of social capital in accelerating poverty alleviation and rural development, facilitating the provision of goods and services, and easing political transition and recovery from civil conflicts.