Fifty patients were identified who, following abdominal aortic operation, developed late complications affecting the vascular graft or endarterectomy and who underwent their first reoperation between 1979 and 1989. Thrombosis was the commonest complication affecting 28 (56 per cent) patients, followed by false aneurysm in 11 (22 per cent), enteric fistula in nine (18 per cent) and graft infection in two (4 per cent). The 30-day mortality rate for reoperation was 8 per cent; longer follow-up revealed mortality rates of 22, 50 and 63 per cent at 1, 3 and 5 years respectively. Thirty-four complications required reoperation within 5 years of the original surgery. Reoperation was needed for 35 patients whose original pathology was occlusive disease and for 15 whose original pathology was aneurysm. The nature of the complication was related to initial pathology; thrombosis was far commoner in those with occlusive disease, and enteric fistula and false aneurysm were commoner in those with aneurysmal disease.