Because it is a chronic, relapsing or progressive disease, multiple sclerosis has an unpredictable clinical course generally spanning 10 to 20 years. During that time, neurologic disability is cumulative. Therefore, it is difficult to evaluate the efficacy of a given mode of treatment in an individual patient. This second part of a two-part series reviews current and emerging modes of therapy for multiple sclerosis. Future treatment directions in multiple sclerosis will require a better understanding of the pathophysiology of the disease. Future therapeutic modalities will also rely on more accurate clinical markers, such as improved magnetic resonance imaging techniques or specific immune markers to follow the disease progression. Part 1 of this series appearing in the November 1999 issue of JAOA included several sections on multiple sclerosis, including an overview, pathophysiology, diagnostic evaluation, and clinical parameters.