In the past few years, ideas of Social Identity Theory and Self-Categorization Theory have been successfully applied to the organizational domain. In this article, the authors provide an overview of these recent developments and present a concept of social identification in organizational contexts, based on these theories. The assumptions of this framework are that (a) social identification in organizational contexts is a multifaceted concept consisting of different dimensions and foci (or targets), (b) higher levels of identification are related to higher productivity and more positive work-related attitudes, and (c) identification is a very flexible concept that is linked to the situational context. The authors present the results of a series of field and laboratory studies in which the proposed relationships are analyzed and, in the main, confirmed.