The evaluation and treatment of 60 intravenous drug addicts with infected false aneurysms of the femoral artery seen at Henry Ford Hospital (Detroit) from 1977 to 1988 were retrospectively reviewed. The most common presenting signs and symptoms were groin swelling and/or mass in 56 (93%) of the patients and pain and/or tenderness in 48 (80%) of the patients. Digital subtraction angiography and standard arteriography showed sensitivities of 92% and 96%, respectively, in the detection of aneurysms. Twenty-three (39%) of the 60 patients had polymicrobial infections. Staphylococcus aureus was isolated in 50 (83%) of 60 cases; 21 (42%) of the isolates were beta-lactam-resistant strains. Anaerobes and aerobic gram-negative bacilli were observed in 12 (20%) and seven (12%) of 60 patients, respectively. Thirty-six (60%) of the patients were bacteremic. All patients received parenteral antibiotics and had surgical resection of their false aneurysm(s). Bacteriologic treatment failures occurred in five of 13 patients who received less than or equal to 15 days of parenteral antibiotics following surgical ligation, as compared with one of 47 who received longer courses (P = .002). Six of 12 grafting procedures were successful, and six of the 60 patients required amputations. There were no deaths. Previously reported cases from the United States medical and surgical literature are reviewed.