The idea of the social contract resonates in many societies as a framework to conceptualise state–society relations, and as a normative ideal which strives to improve them. Policy-makers, development organisations, politicians, social scientists (including anthropologists), and our interlocutors all live with contractarian logics. While generations of political philosophers have debated the concept and its usefulness, the term has also travelled beyond academia into the wider world, shaping expectations, experiences, and imagined futures of state–society relations. An anthropology of the social contract explores ethnographically how this pervasive concept, laden with assumptions about human nature, political organisation, government, and notions such as freedom, consensus and legitimacy, impacts state–society relations in different settings. In this way, the social contract itself – its many emic instantiations, and its political effects – becomes the object of study.