This volume addresses the need to revisit the economic theories from the last two decades that have contributed to the development of a concentrated research agenda on nonprofit organizations. Long neglected as a topic of theorizing and empirical investigation by mainstream economics in particular, these initial theories of nonprofit organizations from the late 1970s and early 1980s continue to shape theoretical and conceptual efforts. Importantly, their influence extends beyond economics and informs sociological and politics science approaches to the set of organizations and institutions located between the market firm and the state agency as well. While the theoretical map of nonprofit research has expanded beyond these early attempts and now include several other major theories such as stakeholder approaches, supply-side or entrepreneurial theories, institutional theories and comparative approaches. This work suggests that it is time to take stock and reexamine some of the basics from which these economic theories operate. This work will be essential to those in the nonprofit sector, organizational management and economics, political scientists and other researchers working with the nonprofit and voluntary sector.