The paper argues that inertia governs the search for explanations of project performance in ways that potentially could impair the quality of feedback obtained about past performance, and thus jeopardise ongoing strategy-making. Based on a critique of relevant literature, the paper presents a novel three-stage framework for analysing connections among inertia and the search for explanations of performance in project-based organizations. This framework helps to show the significance of inertia for the adoption of alternative routes for such search. The framework is illustrated using case study vignettes. These are based on in-depth interviews with senior project management practitioners at two global organizations, about the explanation of project performance (i.e. the attainment or failure to achieve related objectives). Conjectures based on the framework and the vignettes are presented to stimulate further research on how organizations search for explanations of project performance, and on the implications of inertia for organizational and project level learning and strategy.