The ‘Bernstein & Byres Prize’ is the annual prize of the Journal of Agrarian Change (JAC). It is named after the founding editors of the Journal and has been awarded since the 2008 volume. The aim is to celebrate the outstanding contributions received by awarding a prize of £500 donated by our publisher, John Wiley & Sons, Ltd, to the best published paper in any one year. Through this, we also hope to reinforce the remit of the Journal in the field of agrarian political economy and to encourage scholarly work within this tradition. The papers are judged on: (a) their quality as works of political economy; (b) their analytical power; (c) their originality; and (d) the quality of evidence presented and its deployment. The winner of the 2012 prize was selected by a jury consisting of Terence Byres, Henry Bernstein and three members of the International Advisory Board (IAB) of the Journal, based on a shortlist of papers selected by the JAC editors. The three selected members of the IAB vary from year to year. The editors greatly appreciate the evaluators' careful comments, as well as the efforts they put into the task. We are pleased to announce that the winner of the Bernstein & Byres Prize for the best paper published in JAC in 2012 is Subir Sinha for ‘Transnationality and the Indian Fishworkers' Movement, 1960s–2000’ [JAC, 12 (2&3) (special issue on the political economy and ecology of capture fisheries): 364–89]. It is concerned with the fishworkers' movement in the 1960s in India's Kerala state and the role it subsequently played in the formation of national and transnational networks. The paper combines rich concrete material with a distinctive and sophisticated analytical intervention on notions of ‘transnationality’ in recent literature on social movements, and what are seen as their misleading (including teleological) assumptions. It widens the ‘transnationality’ concept by investigating what it labels ‘transnational development regimes’ in fisheries in relation to Kerala: ‘regimes’ or logics and flows of power connecting ‘local’, ‘national’ and ‘global’ planes of action (p. 372). The focus is on the dynamic interplay between ‘above’ and ‘below’, and how this shapes class formation and struggles. The argument for ‘deep and long history’ as necessary in order to grasp the specificities of movements (pp. 386–7), and their ‘conditions of [political] possibility’ (p. 366) is illustrated through a periodization of the ‘transnationality’ of Kerala's fisheries. Contesting a Chayanovian approach, it presents a treatment of class formation and, indeed, class struggle (pp. 372–7). As one of the jury members put it: ‘this is an impressive paper, that is full of analytically astute ideas. Sinha deploys his political economy in a refreshingly critical and thoughtful way.’ Arguably, he pushes the boundaries of ‘classic’ political economy. The political economy categories and methods used to investigate them (e.g. relating to the material conditions and organization of the production process, class formation, relations and struggles) are only some elements, among others, in his analysis. While some of this may be contentious, it is central to why this is a theoretically and empirically perceptive, and enriching, treatment of the topic: an account that breaks new ground. ‘The article stimulated my own thinking’, as another jury member put it. We, the editors, congratulate Subir Sinha as the praiseworthy winner of the 2012 Bernstein & Byres Prize in Agrarian Change.