How does diversity-outgroup contact shape social policy preferences? Despite the large number of studies on the well-known contact hypothesis, the current literature lacks experimental field evidence and behavioural results. In this project, I investigate this relationship in an online environment, a place where polarisation is particularly extreme. In collaboration with an NGO, English-speaking participants are randomly assigned to Zoom conversations with a person from a perceived minority group that differs in religion, gender, sexuality, ethnicity, physical or mental health. The results show that diversity-outgroup contact increases political solidarity with perceived minorities. Mediation investigations based on novel quantitative and qualitative textual analyses indicate a mechanism via the concept of cognitive liberalisation and reduced perceptions of social inequality. In a world of increasing social inequalities and super-diversity, this research project aims to contribute with a solution-oriented approach to social change.