The philosopher Martin Heidegger argued that the truthful life was at risk of being lost in Western technological culture in the name of increasing control, efficiency, and agility.  As the risk is actualised, so the human essence as truth maker is obscured and life itself feels poorer. This thesis draws on Heideggerian philosophy to demonstrate the loss in two dominant styles of contemporary strategic management: the world-picturing and, more recent, agile style. It builds a theory of post-agile strategic practice, which I call adaptive, to address this loss. Consistent with Heideggerian philosophy, I utilise a transformative disclosure methodology and a literary, paradigmatic case reading method to address the questions: Why is agile strategic management so unsatisfying? How do Heideggerian scholars shed light on this dissatisfaction? How do Heideggerians understand the emerging style and what strategic management practices can I propose for the future? After introducing agile strategic management and the impoverishment of life that it fosters, I set out how Heidegger’s philosophy of truth, thinking, and the sacred both sheds light on the problem and suggests a remedy for it. I closely read paradigmatic texts of the world-picturing and agile strategic management styles to demonstrate how business strategy theorisation lines up with extraordinary closeness to Heidegger’s philosophical assessment. I then analyse three Heideggerian prototypes for an adaptive style of strategy practice, concentrating on one paradigmatic text to identify their principal weakness: the omission of the sacred. I illustrate and contrast paradigmatic cases of both the agile and adaptive styles drawn from the beer industry and draw on the adaptive case to construct a theory of adaptive strategy practice, which addresses the problem of the loss of truth, suggesting pedagogical and strategic management practices. I conclude by summarising its findings and contributions, noting some limitations and connections to other studies and suggesting further lines of research