¿Spatial Processing in Navigation, Imagery and Perception¿ Since the decade of the brain cognitive processes have found their way to the study of brain functions and an increasing number of research studies are dealing with the aspect of spatial processing. In fact, a tremendous part of the cognitive domains studied pertain to spatial processing. However, there is also a growing tendency for diversification in relation to the subprocesses underlying spatial processing. Not only are there studies looking at the well known place cells in rats, rabbits and other animals, there is also an increasing number of studies looking at related topics in humans and monkeys such as spatial orientation, spatial construction, and spatial imagery. These studies, although diverse at first glance, have many aspects in common. We are now on the root to understand the underlying neuroanatomy and neurophysiology much better than ever before. This is made possible by the advent of novel techniques such as structural and functional in vivo anatomy, modeling, and several sophisticated behavioral research tools such as virtual reality techniques and simulators. Spatial processing is fundamental for understanding human cognition. However, compared to other domains such as memory, language, and attention the exploration of spatial functions has been understudied in the past years.