In the context of growing interest in social networks and the sociology of graduate education, the authors examine a relational feature of postbaccalaureate study that has received particularly little attention: the doctoral committee. Data on committee memberships speak to multiple theoretical issues and are presumably maintained by most doctorate-granting institutions, yet this information is seldom aggregated or analyzed. Here, the authors draw on records from the University of California, San Diego to illustrate the utility of doctoral committee data for four areas of sociological inquiry: interdisciplinary knowledge production, departmental community, inequality in the workplace division of labor, and variation in student outcomes. For each, the authors present core findings, discuss their implications, and suggest directions for future research.