In some of his more obscure works, Michel Foucault characterises homosexual culture as being connected with an interesting practice of friendship. Since homosexual relationships cannot be derived from existing norms, they are inherently underdetermined, and this means that homosexual culture provides a space for the creation of new types of relationship. Inspired by this practice of social experimentation, Foucault puts forward a concept of friendship based on the collaborative creation of new relationships in marginal spaces. I argue that putting this (...) concept of friendship into practice entails social activism in two ways: first, the creation of new relationships in marginal spaces constitutes a form of localised resistance to social normalisation, and second, because experimentation with relationships presents a challenge to the excessive normalisation of relationships on a societal scale. Friendship, for Foucault, is therefore a resource for both local resistance and large-scale social change. I also argue that Foucault's work on gay culture deserves more scholarly attention because it provides a supplement to his interpretation of the Enlightenment and forges a link between friendship and the aesthetics of existence. (shrink)