This graduation project investigates the stimulation of sustainable behaviour among residents from a housing corporation in Eindhoven, Wooninc., and proposes a program for grassroots infrastructure as a way to support sustainable transitions in neighborhoods.As a partner of the “Duurzaamheidspact Eindhoven” housing corporation Wooninc. formulated the ambition to be more sustainable (Theeuwen, 2018). In order to do so, they not only want to improve their core business but also wants to engage their residents with a more sustainable lifestyle. They adopted the method of ‘De Verborgen Impact’ which includes a train-the-trainer process that trains leading residents, so-called peers, to motivate their fellow residents for a (more) sustainable lifestyle. This led to the key objective for this project: “Design a fitting intervention that peers can use to motivate residents of Wooninc., so that they feel activated to make their lifestyles (more) sustainable.”ApproachBy exploring the design brief and using the designers’ Personal Principles for Good Design the Transition Design method was chosen as the main driver for this design process to understand the project within a broader system context. In addition, the 1:10:100 scheduling technique was applied to allow rapid iterations and to create a concept that is successful and supported by each of the stakeholders. Research & findingsBy conducting four iterative cycles insight in behavioural change was gained from literature and interviews. This resulted in insight in how to reverse internal and external barriers into levers that can be used to support residents in the transition towards a more sustainable lifestyle. This led to the development of the ‘Sustainable Transition’- framework. Which incorporates relevant theories found in literature and maps seven leverage points to inspire for transition towards sustainable behaviour. Based on this framework concept development happened iterative from preliminary vision to the final concept of ‘Onze Verborgen Impact’ Transition Program and Transition Toolkit. The ‘Sustainable Transition’ - framework indicates that to engage residents, as well as peers on their intrinsic motivation all the dimensions of a personal transition should be supported including: motivation and ability, personal values and their position in the process of change. Based on this framework a vision for the final concept was developed: “Making sustainability transparent and accessible (lower the external barriers) by emphasizing the positive side and the advantages of sustainable behaviour (reversing internal barriers). To show that sustainability, in different ways, is accessible for everyone.” The ‘Onze Verborgen Impact’ Transition ProgramTesting prototypes with peers and residents, showed that this concept should not predefine how the peers encounter their fellow residents in their neighborhoods but should enable peers to create their personal approach. This led to the final concept, a transition program called ‘Onze Verborgen Impact’. This program exists out of different elements: - Train: training of the peers by experts- Create: supported by experts peers create their personal approach with which they want to involve residents- Join: residents can participate in the local initiatives set-up by the peers and explore sustainability in their own phase. - Impact: the structure of the program makes it possible to bring new ideas that are generated for improving sustainability at neighborhood level to a higher level - Transition Toolkit: a toolkit with instruments to support the above-mentioned elements such as: three training templates, different recruitment materials and a ‘Mijn Verborgen Impact’ - booklet to support peers and residents in their personal sustainability journey. The final concept taps into the intrinsic motivation of peers by recognizing their personal ideas and creates favourable neighborhood initiatives where residents can experience and discover the benefits of sustainability in their own pace.