Organizational resilience is defined as the organization's ability to absorb strain and preserve or improve functioning despite the presence of adversity. Existing scholarship implicitly assumes that organizations experience and respond holistically to acute forms of adversity. We challenge this assumption by theorizing how adversity can create differential strain, affecting parts rather than the whole of organizations. We argue that relations among those parts fundamentally shape organizational resilience. We develop a theoretical model that maps how the differentiated emergence of strain in focal parts of an organization triggers the movements of adjoining parts to provide or withhold resources necessary for focal parts to adapt effectively. Drawing on core principles of theories about intergroup relations, we theorize three specific pathways—integration, disavowal, and reclamation—by which responses of adjoining parts to focal part strain shape organizational resilience. We further theorize influences on whether and when adjoining parts are likely to select different pathways. The resulting theory reveals how the social processes among parts of organizations influence member responses to adversity, and ultimately organizational resilience. We conclude by noting the implications for organizational resilience theory, research and practice.