Civil society organizations, nonprofits, national and international nongovernmental organizations, and a variety of formal and informal associations have coalesced into a world political force. Though the components of this so-called third sector vary by country, their cumulative effects play an ever-greater role in global affairs. Looking at relief and welfare organizations, innovation organizations, social networks, and many other kinds of groups, Meghan Elizabeth Kallman and Terry Nichols Clark explore the functions, impacts, and composition of the nonprofit sector in six key countries....