Three cases of glucagonoma syndrome were seen in 1 year. Study of the skin biopsies from the first two cases led to a correct diagnosis from skin biopsy of the third case, although it was not suggested clinically. In each case serum glucagon levels were high and a pancreatic tumor was found, with complete remission of symptoms in cases 1 and 3 after resection; case 2 refused surgery and has died. A total of nine skin biopsies from the three patients showed a variety of findings: (a) epidermal necrosis; (b) subcorneal pustules, either isolated or associated with necrosis of the epidermis; (c) confluent parakeratosis, epidermal hyperplasia, and marked papillary dermal angioplasia; and (d) suppurative folliculitis. The clinical lesions in this syndrome vary from bright red macules to annular superficial erosions and flaccid pustules. Similarly, several histopathologic features of the disease can occur, which may represent the progression of the disease. No single histologic feature was specific for the disease, but a combination of the features is probably diagnostic. Therefore, multiple skin biopsies are recommended when this diagnosis is suspected.