This paper reviews all available English language literature on MS from Asian countries published between 1970 and 2005. Although limited data are available, the review reveals that western Asia--including the Middle East--has the highest prevalence of MS across the continent, and that MS in Asia largely resembles conventional MS in western countries. Opticospinal MS (a distinct clinical entity from conventional MS) is more common in eastern Asian regions. Larger epidemiological and genetic studies, with more complete ascertainment in various Asian populations, are needed so that we can understand the diversity of Asian MS