During a 32-month period 94 foot ulcers in 54 diabetic patients aged 38-90 years (mean 64 years) were managed in a specialist foot clinic. Fifty-six percent were men, and they were significantly younger than women; 46% were taking insulin. Mean duration of diabetes was 13.4 years. Comparison with controls revealed a higher prevalence (p less than 0.01) of retinopathy (60% vs 23%), neuropathy (89% vs 31%), vasculopathy (71% vs 34%), arterial calcification (31% vs 20%) and previous lesions (54% vs 4%). There was no difference in quality of diabetic control, or smoking habit. A simple classification of lesions was used. All types yielded mixed cultures of microorganisms (average 2.1 per swab); the flora obtained was affected by systemic antibiotics. Abnormal pressure was judged to have contributed to all lesions occurring in areas of callus. In addition definable trauma precipitated the event in up to 60% of all other types. Lesions in areas of callus were more likely to have healed by the end of the study period, but average time to healing was significantly longer than other lesions. Despite intensive outpatient support, 33 patients spent a total of 1188 days in hospital during the 974 day period, an average of 36 days per patient and 1.2 beds per day. Further research is urgently required to define optimal methods of prevention and treatment of diabetic foot ulcers.