This article centers on a local school reform project aimed at implementing a transformative approach to Education for Sustainable Development (ESD). The study investigates the project in terms of how the design criteria of a continuous professional development program and critical factors of the implementation process influenced the actual teaching practices. Data were collected through interviews with 15 teachers from five schools, and a thematic analysis was conducted. The results showed that the local school reform had limited effect. "Trust" between school actors, "strategic management," and "reflexive collaboration" appeared to be the most important enablers of transferring the reform agenda into teaching practice. "Skepticism," "ambiguous management," and "local contexts" were identified as obstacles, hampering the intended change. A concluding recommendation for implementing transformation oriented ESD through local school reforms and professional development is to add a novel and threefold design criterion to the existing criteria, namely that of "creating and continuously negotiating a shared vision and building trust."