[The explained and the unexplained in dermatological immunology].

By means of classical allergologic and modern immunologic test methods, as well as recent knowledge about antigens and antibody reactions, some dermatoses can be classified with good probability into the allergy types of Coombs and Gell. In other dermatoses much remains unclear. The problems are discussed with regard to several dermatoses and attempts are made to explain some skin alterations by the mentioned immunologic types of reaction.