Of the 309 patients operated on for revascularization of lower extremities 29 (9.4%) had a conventional contrast arteriography that failed to opacify at least one vessel that was found to be patent by color Doppler imaging plus surgical exploration. The indication for vascular imaging was rest pain in 12 patients, claudication in 7, nonhealing ulcers in 3, and gangrene in 3; 4 patients had more than one indication. In 20 (69%) of 29 patients infrapopliteal runoff vessels were the cause for misdiagnosis. In all patients with failed arteriography a total occlusion proximal to the misidentified vessel was present. As a common finding, peak systolic velocities were less than 0.5 m/second in misdiagnosed suprapopliteal arteries and less than 0.25 m/second in infrapopliteal arteries. At operation direct surgical exploration confirmed the diagnosis of color Doppler imaging in all 29 patients. The judgment that the operation was successful was based upon intraoperative arteriography, relief of symptoms, warmness of the feet, palpable pulses, and color Doppler imaging performed one month after the operation. Excellent short-term results were obtained in 27 patients; one early and three late graft occlusions were detected in a mean follow-up of twenty months. In conclusion, color Doppler imaging is an excellent and convenient technique for evaluation of patients with peripheral vascular disease. It demonstrates suitable blood vessels for revascularization that are not seen on contrast arteriography. In the authors' opinion, color Doppler imaging is a clinically useful adjunct to conventional contrast arteriography and should be performed in patients in whom arteriography has failed to show any suitable target vessel for revascularization.