A variety of epithelioproliferative benign neoplasms, both trivial and life-threatening, are caused by subtypes of human papillomaviruses. Interferons objectively regress HPV-induced warty disease and affect the regrowth of the transformed epithelium. Interferons effectively control the most serious and potentially life-threatening papillomavirus associated diseases, respiratory papillomatosis and genital warts, but not without the anticipated side effects associated with this potent biological weapon. It is entirely possible and even likely that individual species of interferons act preferentially on certain cells, tissues or organs in response to particular viruses. Combined therapies, such as surgery in combination with interferon, or podophyllin in conjunction with interferon alfa-n1, may prove most efficacious.