While most innovations are developed in organizations, there is a wide-spread consensus that the organizational institutionalization of Responsible (Research and) Innovation is limited. This may partly be the case because we lack an understanding of what factors drive or impede the institutionalization of such responsibility-related changes and how they interact. In this paper, we draw from various institutional entrepreneurs’ experiences, who worked within eight organizational change labs, to explore the dynamic institutionalization of Responsible (Research and) Innovation. Our study identifies 29 factors highlighting some of the intricate, dynamic, and ‘messy’ complexities found in organizations. We conclude by offering some reflections on the role of institutional entrepreneurship for Responsible (Research and) Innovation.