["Journal for the Theory of Social Behaviour, Volume 56, Issue 3, September 2026. ", "\nABSTRACT\nProsocial behaviour is a topic of concern within sociology and the social sciences more broadly. Though defined in various ways, the dominant theme of existing definitions of prosociality centres the causal power of an act in producing real or intended benefits for some other agents, at a cost to the agent that performed the act. Under this conceptualisation, many phenomena of sociological importance have been studied, from the micro‐level of personal donation choices to the meso‐level and macro‐levels of social movement organising. Despite the theoretical and practical importance of prosocial behaviour to social life, this conceptualisation does not perform well as a practical guide to understanding prosociality unless it is supplemented by controversial and non‐empirical assumptions. This paper proposes an alternative conceptualisation of prosociality that avoids these failures while retaining the successes of the consequentialist approach. This alternative conception builds on pre‐existing sociological research on the dynamic boundaries of the self, our embeddedness in structures of social relations and how situations prompt us to act in accordance with our identities. These research traditions point us towards a systematic study of patterns of prosocial relations, and how those patterns interact with other social structures.\n"]