Sufficient safety and efficacy data have been obtained on a live varicella vaccine (Varilrix, Smith Kline-RIT) derived from the Oka-strain attenuated varicella-zoster virus to justify its recent licensure in several European countries for use in special indication groups. This review article summarizes the data obtained in Japan, Europe, and the United States. In addition, a survey of the published literature on clinical studies performed on as yet unlicensed Oka-strain varicella vaccines produced by the Biken Institute and Merck Sharp & Dohme is presented.