Delia Baldassari is the Julius Silver, Roslyn S. Silver, and Enid Silver Winslow Professor in the Department of Sociology at New York University. Professor Baldassarri’s research interests are in the fields of Economic Sociology, Political Sociology, Social Networks, and Analytical Sociology. Her current research projects include a study of the emergence of cooperation in complex societies, focusing on the empirical case of ethnically heterogeneous communities and a book project investigating the demographic and social network bases of partisanship in American public opinion. Professor Baldassari can be reached at delia.b@nyu.edu.