This paper reports the results of a literature review examining the effects of exercise on mental health and well-being. Throughout history many societies, ancient and modern, have used exercise as a means of preventing disease, and promoting health and well-being. There is evidence that exercise is beneficial for mental health; it reduces anxiety, depression, and negative mood, and improves self-esteem and cognitive functioning. Exercise is also associated with improvements in the quality of life of those living with Schizophrenia. However, exercise is seldom recognized by mainstream mental health services as an effective intervention in the care and treatment of mental health problems. There is evidence to suggest that exercise may be a neglected intervention in mental health care.