Faced with increased pressure due to the earthquakes in Groningen and global warming, the Netherlands government has decided to discontinue the production of and completely transition away from natural gas by 2050. This requires the transformation of the 95% of houses that are currently heated using natural gas into ones that are heated using greener energy alternatives. To affect the requisite change, the government’s top-down, policy-driven efforts need to be complemented with bottom-up, socially-driven interventions that lead to the institutionalisation and large-scale adoption of the greener energy alternatives. This project aims to stimulate this bottom-up institutionalisation and activate residents towards the energy transition using the phenomena of social influence and social contagion. The focus on social influence and social contagion follows from the extensive literature that highlights the significant role of social norms, social proof, social context and social networks on an individual’s decision-making and attitude formation; as well as in changing behaviours. The project draws on complex contagion theory to activate residents. Reyeroord (a pilot neighbourhood in Rotterdam) is used as a case study to understand the municipality’s efforts and residents’ motivations & apprehensions towards the energy transition; as well as to understand people’s social identities and networks – the building blocks of social influence. Analysis reveals the prevalence of different barriers under the key themes of trust, loss/ risk perceptions, understanding & awareness which lead to procrastination of decision-making amongst residents. Thus, overcoming procrastination by mitigating the underlying apprehensions and barriers forms the key goal for Reyeroord. In order to help the Municipality(s) to overcome these apprehensions using social contagion, the ‘Design for social contagion’ framework and toolkit are developed. The framework provides actionable steps that help in visualising and shaping the contagion of the target behaviour. The toolkit helps in designing interventions within the process outlined in the framework. It consists of a deck of inspiration cards, a set of canvases and a design handbook; to be used during a creative session. The inspiration cards capture the design criteria, design principles and design components that each intervention must fulfill, follow and consist of, respectively. Additionally, the cards include examples of persuasive strategies that can be used to design the interventions. The canvases guide the design process from problem definition, brainstorming, concept generation to detailing. The handbook outlines how to use the toolkit. From the perspective of transitions (transition design), the project, its outcomes and the underlying principle of social contagion provide a new perspective and leverage point to untangle (loosen) the complex knot between the interconnected social, technical, financial and political lock-ins and steer systemic change. On the other hand, it bridges the gap between academia and practice by providing actionable steps to shape contagions, qualitatively.