We report on a 17-year-old patient suffering from generalized verrucosis. This diagnose had been confirmed by means of light microscopy, electron microscopy, and DNA hybridisation (HPV type 2). The study of immunological parameters revealed reduced numbers of T-lymphocytes, especially of helper-T-cells. Skin tests with recall antigens were normal. Three brothers of our patient showed slight reduction of helper-T-cells. Treatment with topical retinoic acid was not effective. Treatment with alpha-interferon i.m. intralesionally was effective in the beginning, but two weeks after onset of therapy no further improvement could be achieved. Discontinuation of therapy was followed by a relapse. Tigason which was given thereafter led to flattening of the warts but failed to bring about complete regression within the following four months.