Abstract:Transitions to deal with the grand challenges of contemporary societies require novel kinds of leadership, which can both stimulate novel organizational practices and changes in practices and structures in the organization's context. This article seeks to understand how (changes in) the external structural context may influence organizational-internal transformative leadership and vice versa, and what kind of work is implied in leadership to transform current business models. It uses notions from literature on relational leadership and transformative leadership as sensitizing concepts. It then explores the leadership work in two case studies, on fishing in Portugal and care farming in the Netherlands. We find a dialectic interplay of the interactions between leaders and others on the one hand, and contextual changes on the other. Using a system-building perspective from innovation system literature, that interaction is driven by the quest to establish legitimacy and market formation and acceptance, knowledge and other resources for innovations.