A prospective study was undertaken to evaluate the clinical and hemodynamic effects of aortofemoral Dacron reconstruction in patients with multilevel disease (i.e. aortoiliac and femoropopliteal occlusive disease). Thirty nine patients underwent, apart from clinical evaluation, segmental plethysmography and Doppler pressures before operation, immediately after operation and again at 3 and 6 months. All patients improved by the reconstruction, but 12 (31%) continued to complain of disabling claudication during normal daily activities. The mean ankle pressure and thigh pressure index improved by 37.5%. This was accompanied by a decrease of peak flow time, an increase of peak flow and an improved recovery during reactive hyperemia. Furthermore an additional significant rise of the ankle pressure index was noted between 3 and 6 months. Continuing claudication was always associated with both initial and late hemodynamic failure (the criterium for hemodynamic success was defined as an increase of the ankle pressure index with more than 0.1). Hemodynamic success resulted unvariably in clinical success. However 4 patients were clinically symptomfree, although they had to be classified as hemodynamic failures. It is concluded that a significant number of patients fail to obtain complete relief after proximal reconstruction. Preoperative hemodynamic studies may provide additional information, but hemodynamic and clinical results do not always correlate with each other.