This book is about mental imagery and the important work it does in our mental life. It plays a crucial role in the vast majority of our perceptual episodes. It also helps us understand many of the most puzzling features of perception (like the way it is influenced in a top-down manner and the way different sense modalities interact). But mental imagery also plays a very important role in emotions, action execution, and even in our desires. In sum, there are very few mental phenomena that mental imagery doesn’t show up in—in some way or other. The hope is that if we understand what mental imagery is, how it works and how it is related to other mental phenomena, we can make real progress on a number of important questions about the mind. This book aims at an interdisciplinary audience. As it aims to combine philosophy, psychology, and neuroscience to understand mental imagery, I have not presupposed any prior knowledge in any of these disciplines. As a result, readers with no background in any of these disciplines can also follow the arguments.