As a worldwide and transnational movement, the Transition Town movement formed in the mid-2000s. Initially, its protagonists concentrated on the transition to a post-fossil city. Within a decade, however, diverse civil society initiatives have emerged that are active in many domains relevant to urban development. With their holistic approach, their normative orientation towards sustainable development and their participation-oriented activities, Transition Town Initiatives (TTIs) often adopt the role of intermediaries in local contexts. This postmodern type of change agent, also called "neo-intermediaries" (Beck et al., 2017, pp. 45-51), is a civil society actor who seeks to initiate social change from below, follows a new understanding of civic engagement and uses more flexible forms of networking and communication. As change agents, these intermediaries mediate between state actors (local politics and administration) and non-state actors (civil society, business and academia) at the urban level and thus establish new partnerships for sustainable urban development. In the project "New partnerships for sustainable urban development? Potentials of Transition Town Initiatives", the IOER is investigating the potentials and challenges which arise from the cooperation between Transition Town initiatives and municipal actors and how they contribute to urban sustainability transitions. The project is funded by the Federal Association for Housing and Urban Development (vhw - Bundesverband für Wohnen und Stadtentwicklung e.V.).