Monoclonal antibodies are of growing interest as treatment options for immune-mediated diseases in neurology. As our knowledge of immunological principals increases, we learn to modulate specifically mechanisms of pathogenesis by the use of monoclonal antibodies. It is clearly desirable to improve efficacy in disease treatment without increasing toxicity by using drugs with more specific modes of action. Natalizumab was the first monoclonal antibody approved in the field of neurology for treatment of relapsing remitting multiple sclerosis (MS). Several other monoclonal antibodies are currently under investigation. Alemtuzumab, a monoclonal antibody targeting CD52, is a highly promising agent currently being studied in two phase III clinical trials. In this review, data from the recently published phase II clinical trial in the treatment of early relapsing remitting MS is summarized and analyzed in light of the development of alemtuzumab for MS and its potential role in treating this disease is discussed.