This paper disputes the claim that our understanding of others is enabled by a commonsense or 'folk' psychology, whose 'core' involves the attribution of intentional states in order to predict and explain behaviour. I argue that interpersonal understanding is seldom, if ever, a matter of two people assigning intentional states to each other but emerges out of a context of interaction between them. Self and other form a coupled system rather than two wholly separate entities equipped with an internalised capacity to assign mental states to the other. This applies even in those instances where one might seem to adopt a 'detached' perspective towards others. Thus 'folk psychology', as commonly construed, is not folk psychology.