This article emerges from the simple observation that community-based social and environmental activists often engage with practices of mindfulness, either personally or collectively. It draws on two case studies, a UK-based Transition initiative and a community of social entrepreneurs in Germany. On the surface, social and environmental activists, committed to change in the ‘real world’, outward facing and public, jar with practices of ‘mindfulness’: personal and interior actions –‘private’. We argue that post-foundationalist understandings of community, particularly Nancy’s being-in-common – popularised within geography as ‘community economies’ – and the philosophical and spiritual roots of mindfulness are two lines of thought that provide clues to this co-occurrence. Going beyond understandings of collectivity that build on the coming together of preformed individuals or presuppose a common substance, we set the (Westernised) Buddhist influences on mindfulness, specifically the notion of interbeing, side by side with Nancy’s being-incommon. This article argues that both the political and spiritual aspects of activism are integral parts of social change. It concludes that post-foundational and Buddhist-inspired lines of thought cross-fertilise and chart a course towards transformative mindfulness.