Multiple, overlapping logics of urbanisation are transforming Tamil Nadu's coast. Real estate, infrastructure, tourism, and urban beautification plans are putting unprecedented pressure on the coastal commons. Fisherfolk, whose everyday life and survival is rooted in the commons, are at the centre of these processes of coastal urbanisation. Faced with the prospect of losing access to these spaces, fisherfolk are drawing upon their customary knowledge and new satellite mapping techniques to assert their rights to land and livelihoods.