In this study of high-poverty schools in Trinidad and Tobago, we (1) identified recurring patterns and generative mechanisms for successful principal leadership and (2) explored the utility of transformational, shared, and instructional leadership models. We argued that situational and country context are central to understanding school leadership and that the universality of some models might be limited. Using the lens of critical realism, we gathered evidence from a multiple case study of seven high-poverty schools. From the data, we constructed theory bridging leadership constructs of the global North with emergent local patterns and constructions. We found three meanings for successful leadership within this context, labelled as integrative, transformational and enabling, and academic-focused. The meanings attached to the in-vivo labels were consistent with the core components of shared, transformational, and instructional leadership. We extended these leadership meanings to describe specific activities and acts. Unique to this context was the data-centric focus of transformational leadership and the use of shared leadership as an early improvement strategy. Notably, however, academic-focused leadership was evident at only a few sites, possibly explaining the overall limited improvement trajectory.