The involvement of the humoral and cell-mediated immune systems in the regression of wart infection has been investigated extensively in recent years. This review examines the supporting evidence for the roles of humoral and cellular immunity in wart regression and its possible implications. From the available data it does not appear that a conclusion can be drawn that only humoral or cell-mediated immunity is involved, or that both are essential, in the regression of wart infection. Studies by several investigators, however, suggest that, since agents known to stimulate the cell-mediated immune system have been reported to be followed by the successful resolution of warts, the cell-mediated immune system appears to play a critical role in wart resolution. It may be that the direction which should be taken in eradication of warts resistant to conventional modalities of treatment is one which relies upon the stimulation of the patient's immune system in a very specific manner. Probably the most efficient way to accomplish this, based on available data, would be by autogenous vaccination. Following the patient's humoral and cell-mediated immune response prior to, during, and following treatment with autogenous vaccination may help to elucidate the precise mechanism by which the successful resolution of warts occurs.