This chapter presents three cases that demonstrate a variety of interactions between residents and expert leaders in fostering sustainability innovations in cities. It looks at sustainable cities in Sweden, Japan, and the Netherlands, focusing on common principles that may help explain their success as well as the role of environmental education and learning in these efforts. All three examples engage municipal nonprofit and government agency leaders with residents in many different ways. Leaders and residents learn about sustainability as they build skills for participatory decision making. They offer ideas and realize that their contributions matter. The cases have outlived their inception phase and continue to grow and improve their outcomes despite setbacks, changing circumstances, and even opposition. The chapter explains how monitoring the outcomes of such innovations, including through citizen science and social learning, can contribute to their effectiveness.