This is a constructive critique of Habermas’s account of rationality, which is central to his political theory and has sparked theoretical and empirical research across academia. Habermas and many critical theorists caricature means-ends rationality (the ability to pick good means to ends), e.g. by wrongly depicting it as egocentric. This weakens Habermas’s attempt to distinguish means-ends rationality from his hugely important and influential idea of communicative rationality (roughly, the rationality of genuine discussion). I suggest that sincerity and autonomy, rather than (...) non-egocentrism, are the key distinguishing features of communicative rationality. This shows that communicative rationality actually overlaps with means-ends rationality. Indeed, means-ends rationality is needed by critical theorists, as I exemplify by showing its use in deliberative democracy. Moreover, means-ends rationality will be present in discourse ethics, as I show with the example of moral discourse about gay marriage. My article thus challenges decades of what Habermas and critical theorists have written on means-ends and communicative rationality, but I stay broadly true to – and hopefully improve – Habermas’s account of rationality. (shrink)