Herreros examines from the ground up, and from first principles, how social capital is formed. He gives special attention to "particularized trust," the byproduct of associational participation, and its relationship to generalized social trust. He argues that social capital, the resources drawn from obligations of reciprocity and information, derives from participation in social networks, including voluntary associations. The book uses game theoretical models to highlight mechanisms facilitating the formation of trust and, in contrast to many theorists, Herreros places emphasis on the role of the state in the creation of social capital. The theoretical arguments are tested empirically using survey data and historical cases. This sophisticated analysis is sure to generate debate.