This review of cognition in strategic management research takes as its starting point the appreciation of the seminal paper, ‘Competitive groups as cognitive communities: the case of Scottish knitwear manufacturers’, by Porac, Thomas and Baden-Fuller on cognitive categorization of competition, published in the Journal of Management Studies only 20 years ago. In this paper, I reflect on the context in which their paper emerged, the impact it has had, and the future paths that research on cognition in strategy might take. In doing so, I highlight the challenges associated with establishing cognition as a legitimate factor in strategic management (alongside the traditional explanations of capabilities and incentives) and of showing the causal relationship between cognition and strategic outcomes. Subsequent work in cognition explored the dynamic relationship between cognition, capabilities, and incentives, and, in process models of framing, linked cognition with political action. Rather than managerial cognition becoming its own independent field, cognitive concepts have diffused throughout work in many different managerial fields, leading to a proliferation of terms, concepts, and approaches. I conclude by exploring some of the paths that research in cognition and strategy is taking in the present day – particularly those involving studies of the construction of markets and categories, each of which are themes that the work by Porac, Thomas and Baden-Fuller brought to our attention.