Cooperation allows strategic gains in access to resources and risk sharing, especially in technological development efforts. However, market pressures, such as the search for differentiation, can mitigate the decision to engage in cooperative activities. This article describes and explains how alliances and partnerships are sustained in an environment that pushes for value creation through differentiation. As environments where multiple organizational actors meet geographically to share and compete for resources, innovation ecosystems form a relevant object of study to answer this question. This article applies the theoretical lens of institutional work to analyze two innovation ecosystems located in different socio-economic contexts: Sophia Antipolis in France and Tecnosinos in Brazil. The results indicate that the institutional work of social structuring, normative systems and cognitive coherence can support cooperation as a strategic option for technological development in innovation ecosystems. The article provides three contributions: it informs the literature on cooperation strategies with 10 practices that support cooperative action; it portrays narratives of a set of actors that could promote practices aimed at institutionalizing cooperation; it proposes a model for cooperation resilience in innovation ecosystems.