Vision is the perceptual sense that is most highly developed in humans, and a large proportion of the brain is dedicated to this sense. Brain injury can lead to a wide range of visual impairments that can have important consequences for the individuals affected. To detect, understand, and provide appropriate rehabilitation for brain-based visual impairments, an understanding of the complexity of how the brain processes vision is necessary. This chapter provides a comprehensive description of how vision is processed in the brain. This includes a description of how cells in the back of the eye transform information about light coming from the surroundings into neural signals, how this information is projected to the visual cortex in the back of the brain for basic processing, and how the information is further processed into meaningful representations along a ventral and a dorsal pathway. Impairments associated with damage at different stages of visual processing are described along the way, including visual field deficits, cerebral achromatopsia, visual object agnosia, prosopagnosia, pure alexia, simultanagnosia, optic ataxia, ocular apraxia, and topographical disorientation. Recommendations related to the assessment and rehabilitation of brain-based visual impairments are also provided.