The aim of this article is to develop a model of change in urban context to map key steps towards changing an institutional logic: How can new ideas that aim at changing the dominant logic become practice in a city? To this end, the article explores the innovation process of institutions, thereby bringing together areas of research on institutional entrepreneurship, innovation processes, and transformation. Our model interlinks invention, innovation and adoption of new institutions to achieve a new institutional logic for more sustainable development in a city. We introduce ‘workset’ as an interim step between action and practice and identify local adopters as key for diffusion. We illustrate our framework using a case study of urban institutional entrepreneurship in the socio-economic system of a German city. Our findings indicate that the roles of local institutional entrepreneurs and local adopters partly overlap, that worksets are crucial for broader diffusion of new institutions, and that a robust design supports the adoption of the institutional innovation.