Our minds have physical effects. This happens, for instance, when we move our bodies when we act. How is this possible? Thomas Kroedel defends an account of mental causation in terms of difference-making: if our minds had been different, the physical world would have been different; therefore, the mind causes events in the physical world. His account not only explains how the mind has physical effects at all, but solves the exclusion problem - the problem of how those effects can have both mental and physical causes. It is also unprecedented in scope, because it is available to dualists about the mind as well as physicalists, drawing on traditional views of causation as well as on the latest developments in the field of causal modelling. It will be of interest to a range of readers in philosophy of mind and philosophy of science. This book is also available as Open Access.