Multiple sclerosis (MS) is a complex, incurable disease. Treatment consists of lifelong disease and symptom management. FDA-approved therapies for relapsing MS include subcutaneous (SC) interferon beta-1b (IFNbeta1b, Betaseron), IM interferon-beta-1a (Avonex), SC interferon-beta-1a (Rebif), glatiramer acetate (Copaxone), and mitoxantrone (Novantrone), all of which are known as disease-modifying agents (DMAs). DMAs that can be initiated and continued on a long-term basis can be referred to as platform therapies. During periods of disease instability with increased disease activity, corticosteroids or immunosuppressive agents can be used in combination with appropriate DMA platform therapy to help control symptoms. To date, long-term comparative studies of DMAs are not available. However, based on the effects of these agents on disability progression, relapse rates, MRI outcomes, and neutralizing antibodies observed in phase III randomized clinical trials, IFNbeta1a products are the DMAs of choice for platform therapy for MS. Evidence indicates that IFNbeta1a may also be beneficial in the early stages of the disease. Research is ongoing to identify other appropriate add-on agents (e.g., antigen-specific therapies) to be used in combination with existing DMAs to effectively manage MS.