Our ability to be conscious of the world around us is often discussed as one of the most amazing yet enigmatic processes under scientific investigation today. However, our ability to imagine the world around us in the absence of stimulation from that world is perhaps even more amazing. This capacity to experience objects or scenarios through imagination, that do not necessarily exist in the world, is perhaps one of the fundamental abilities that allows us successfully to think about, plan, run a dress rehearsal of future events, re-analyze past events and even simulate or fantasize abstract events that may never happen. Empirical research into mental imagery has seen a recent surge, due partly to the development of new neuroscientifc methods and their clever application, but also due to the increasing discovery and application of more objective methods to investigate this inherently internal and private process. As the topic is cross hosted in Frontiers in Perception Science and Frontiers in Human Neuroscience, we invite researchers from different fields to submit opinionated but balanced reviews, new empirical, theoretical, philosophical or technical papers covering any aspect of mental imagery. In particular, we encourage submissions focusing on different sensory modalities, such as olfaction, audition somatosensory etc. Similarly, we support submissions focusing on the relationship between mental imagery and other neural and cognitive functions or disorders such as visual working memory, visual search or disorders of anxiety. Together, we hope that collecting a group of papers on this research topic will help to unify theory while providing an overview of the state of the field, where it is heading, and how mental imagery relates to other cognitive and sensory functions.