This volume builds understanding of practices in youth and community development that create or build social capital assets at the individual, group, and community levels. The authors explore whether programs contribute to the development of social capital at the individual and community scales, thereby fostering and enhancing positive youth development as well as community development. It includes articles on defining and measuring social capital through instruments designed to document impact and also to engage program participants. The authors then discuss program practices that build social capital in a wide range of youth development settings, from community-based service-learning to 4-H community clubs. Finally, they focus on building social capital in particular contexts, including work in rural communities with the most vulnerable youth. The volume is designed to help practitioners: Refine their dual focus on youth and community development Clarify constructs that help translate the public value of positive youth development to community stakeholders Provide examples of practices that link youth and youth programs more intentionally to the social relationships that knit communities together. This is the 138th volume of New Directions for Youth Development, the Jossey-Bass quarterly report series dedicated to bringing together everyone concerned with helping young people, including scholars, practitioners, and people from different disciplines and professions.