Philosophy of psychiatry has boomed in the last few years. We are now seeing a growing literature on the nature of psychiatric explanation, including work that makes contact with longstanding disputes in the philosophy of science as well as more specific work on mental disorders. This paper looks at some recent work on both representing and explaining mental illness. An emerging picture sees explanation of mental disorder as first constructing causal-statistical networks that represent disease pathways as they unfold in time, and then choosing strategies for causal explanation. The epistemic problems in psychiatry are huge, and they arise from the extreme variety in the causes and trajectories of mental disorders across patients. Existing concepts of levels of explanation and mechanism may seem like an obvious epistemic armoury, but they may not fit psychiatry very well, and philosophical theories of psychiatric explanation stress different ways of trying to understand robust patterns amid the individual variation.