Multiple sclerosis (MS), a neurologic disorder that affects 400,000 persons in the United States, consists of an inflammatory and a neurodegenerative phase. Treatment options now approved by the FDA specifically target the inflammatory phase of MS and include immunomodulators (i.e., interferon betas and glatiramer acetate) and an immunosuppressant, mitoxantrone. This article discusses the methods of monitoring disease progression using disability scales and MRI and reviews the clinical efficacy and tolerability of the FDA-approved therapies. All of the immunomodulators are approved for the treatment of relapsing forms of MS. Only mitoxantrone is approved for the treatment of worsening relapsing-remitting MS, secondary progressive MS, and progressive-relapsing MS. Early treatment with these disease-modifying agents is desirable to reduce the progression of the disease and to limit long-term disability.