KENNETH PREWITT is Carnegie Professor of Public Affairs in the School of International and Public Affairs at Columbia University. MATTEI DOGAN is senior fellow at the National Center for Scientific Research in Paris, and chair of the research committee on Comparative Sociology of the International Sociological Association. STEVEN HEYDEMANN is director of the Center for Democracy and the Third Sector and political scientist in the Department of Government at Georgetown University. STEFAN TOEPLER is assistant professor of nonprofit studies in the Department of Public and International Affairs at George Mason University.