This chapter surveys research on social capital. We explore the concepts that motivate the social capital literature, efforts to formally model social capital using economic theory, the econometrics of social capital, and empirical studies of the role of social capital in various socioeconomic outcomes. While our focus is primarily on the place of social capital in economics, we do consider its broader social science context. We argue that while the social capital literature has produced many insights, a number of conceptual and statistical problems exist with the current use of social capital by social scientists. We propose some ways to strengthen the social capital literature.