Multiple sclerosis is one of the most frequently observed neurological causes of progressive disability in early to middle adulthood. The disease is variable in its presentation and course, affects roughly 100 to 300 per 100,000 persons within the US alone and is slightly more common among females than males. Multiple sclerosis places substantial burdens on patients, families and caregivers. Its presentation includes disturbances in cognitive abilities and psychiatric functioning, as well as motor difficulties. This article reviews the current literature on the neuropsychiatric manifestations of multiple sclerosis. Cognitive domains discussed include general cognitive functioning, learning and memory ability, attention, processing speed, executive functioning, visual perceptual ability and language functioning. Attention is also given to alterations in neuropsychiatric functioning associated with disease progression and across various disease subtypes. In addition, reports are also reviewed regarding various psychiatric disturbances, affective changes, quality of life issues and fatigue and pain in individuals with multiple sclerosis. Finally, factors pertaining to pediatric populations in multiple sclerosis are addressed.