My project in this paper is to extend the interventionist analysis of causation to give an account of causation in psychology. Many aspects of empirical investigation into psychological causation fit straightforwardly into the interventionist framework. I address three problems. First, the problem of explaining what it is for a causal relation to be properly psychological rather than merely biological. Second, the problem of rational causation: how it is that reasons can be causes. Finally, I look at the implications of an interventionist analysis for the idea that an inquiry into psychological causes must be an inquiry into causal mechanisms. I begin by setting out the main ideas of the interventionist approach.