[New possibilities of phototherapy (author's transl)].

Absolute and relative indications for phototherapy have to be distinguished. Absolute indications, where no better treatment is available, are psoriasis, mycosis fungoides and - according to newer observations - atopic dermatitis. Relative indications, where phototherapy is an additional therapeutical possibility, are acne, certain types of dermatitis and of urticaria. Acute and chronical side effects are discussed and an outlook on the possibilities of phototherapy is given.