During 2003 and the first half of 2004, CDC received reports of eight varicella-related deaths. The age of the decedents ranged from 1 to 40 years. Six of the eight deaths occurred among children and adolescents aged <20 years. The cases were reported from Arizona (two), Maryland (two), Arkansas (one), New Hampshire (one), Ohio (one), and New York City (one). Six deaths occurred in unvaccinated persons. Vaccination status of the remaining two persons could not be determined. This report describes clinical data for three of the fatal varicella cases in children, reported from Arizona, Arkansas, and New York City; all three patients were susceptible and unvaccinated, but otherwise healthy. The three other children and adolescents, not described in detail in this report, were immunocompromised as a result of at least one preexisting condition. The findings in this report underscore 1) the importance of timely routine vaccination of children aged 12--18 months and catch-up vaccination of older susceptible children and adolescents according to current recommendations and 2) the need for timely and complete national varicella death surveillance.