Multiple sclerosis is a chronic, autoimmune disease that affects the nervous system. It is thought to be caused by an abnormal inflammatory process that is triggered in susceptible individuals by a combination of environmental, lifestyle, infectious, and genetic influences. The onset of multiple sclerosis is age-related and affects women far more than it does men. It is a progressive disease and many people who develop MS will eventually have significant disabilities. The four categories of MS are discussed, including drug and non-drug treatment.