Organizational adaptation is a ubiquitous concept in management and organization research. Discussed in many theories, sometimes under different labels, the notion of adaptation is related to organizations being congruent to the environments within which they operate. Research traditions including behavioral theory (see A Behavioral Theory of the Firm), contingency theory as explained in Differentiation and Integration in Complex Organizations, population ecology (see The Population Ecology of Organizations), institutional theory elaborated upon in both Institutionalized Organizations: Formal Structure as Myth and Ceremony and The Iron Cage Revisited: Institutional Isomorphism and Collective Rationality in Organizational Fields, resource dependence (see The External Control of Organizations: A Resource Dependence Perspective), and evolutionary economics (see An Evolutionary Theory of Economic Change) all address organizational adaptation—though they emphasize different mechanisms. Adaptation, regarded as the strategic choice that organizations make, is often contrasted with the notion of selection driven by the determinism imposed by environments (see Organizational Adaptation: Strategic Choice and Environmental Determinism). Adaptive organizations are those able to obtain congruence both within organizations, reflected as congruence in internal functions and strategies, and across organizations, reflected as congruence with the needs of the external environment. The form of adaptation is also particularly relevant. Organizational theory has viewed adaptation as a state, an ability, and as a process. States of adaptation discuss stability and adaptation at points in time. From states of adaptation, adaptive abilities determine the impetus of adaptation and the locus of adaptation within organizations. Finally, the adaptation processes describe the means by which organizations adapt the challenges they face in negotiating new positions within environments. Research has covered each of these areas and this bibliography is organized primarily around forms of adaptation to elaborate on the ways in which it has been viewed by organizational theory and strategy scholars. The variety of research traditions examining organizational adaptation have not always aligned, however. Each research tradition seeks to explain different outcomes, from survival to performance to change. Thus, across theoretical traditions, the adaptation construct has been measured in many different ways—and often not as congruence with the external environment. In fact, this represents one of the challenges that recent research has identified as holding back progression of the adaptation research agenda. As such, this bibliography concludes with a section on issues in adaptation research in order to assist researchers in pursuing research in this area.