I integrate stereotype-fit and social interdependence theories to propose a model explaining how and why decision makers discriminate in personnel decisions. I suggest that decision makers draw on stereotypes about members of different social groups to infer candidates’ task-related ability. Decision makers perceive candidates having a greater ability required for the task as less (more) instrumental to their personal outcomes if they expect to compete (cooperate) with the candidate, which in turn shape the pattern of discrimination. The current research demonstrates the importance of considering the largely overlooked role of interdependent relationships within the organization for understanding discrimination in organizations.