In this paper we compare the emerging field of open strategy to the established field of open innovation in order to facilitate their cross-fertilisation both in research and practice. Taking a communication-centred perspective, we argue that in both fields ‘openness’ concerns opening-up the communication process towards previously excluded individuals. On the basis of our review of the literature, we introduce a general framework that distinguishes between two dimensions of openness in terms of the direction that communication takes: sharing communication content with external participants and audiences and receiving communication content from external participants and audiences. Using the two dimensions of sharing and receiving, we map documented cases of empirical research in both fields and identify different forms of openness in processes of open innovation and open strategy. As we will show, in the material that we examined, in most of the cases of open strategy sharing and receiving are combined, while in many cases of open innovation we identified only one dimension. We suggest that this difference arises because, unlike innovation, open strategy typically involves joint sensemaking and thus a bidirectional communication process. Drawing on our findings, we put forward three propositions to provide a foundation for future empirical research on phenomena of open innovation and open strategy.