This report focuses on the start-up company HOMIE B.V. (hereinafter refered to as “HOMIE”). HOMIE is a household appliance company, currently focused on washing machines, that provides its products through a pay-per-use model. Here the customer does not buy the product, but only pays a small fee for each time that the product is used. Through this model, HOMIE aims to generate sustainable customer behaviour. The customer is motivated by the payment system to wash less often. Addtionally, HOMIE asks different prices for different washing temperatures, and the company provides customers with feedback mailings, all to motivate sustainable washing. The aim of this project was to answer two main research questions: To what extent is HOMIE already creating sustainable customer behaviour through the currently implemented design interventions? How does the environmental impact compare to average washing machine use, and what level of change is reached through the current interventions? Which design solutions can provide the best results in terms of environmental impact, customer satisfaction and business viability? Which design and business model solutions can provide the best results for creating the sustainable customer behaviour interventions? To answer the first question, a literature review was conducted to understand what sustainability entails in the case of washing machines, and which factors influence it. Nationwide washing data was then collected, and compared through statistical analysis to the washing data of HOMIE customers. Although the monthly mailings did not have a statistically siginificant effect on the washing behaviour, there was still a statistically significant difference between certain washing behaviour aspects of HOMIE customers and the national averages. Gaining the necessary insights for the second research question also started with a literature review, aimed at understanding the relevance of customer behaviour to the environmental impact of washing machine use. The literature review also explored existing research on the topic of how to change customer behaviour, as a foundation for developing new solutions. An internal analysis of HOMIE as a company, and an external analysis of the competitive landscape were conducted to understand the strategic environment in which new concepts would have to be released. A series of interviews was used as additional research to understand users’ current washing behaviour. New concepts were then developed in an idea generation process, and one of these was chosen to be explored further. Using questionnaires, the concept was evaluated in regard to some of the most important criteria that were established for this project. After this, the concept was improved using outcomes from the questionnaire, after which the concept was evaluated again. All in all, the project provides an insight into the effects of the business model HOMIE uses to generate sustainable washing behaviour, and also delivers new solutions aimed at maximising value for creating environmental impact improvement, for delivering customer value and for creating business value.