Duplex scanning is becoming increasingly important in the diagnosis and follow-up of arterial lesions, though most surgeons and radiologists currently still prefer diagnostic angiography prior to percutaneous transluminal angioplasty (PTA). We performed PTA based on Duplex scanning alone in 31 selected patients during the last 6 months of 1991. Seventeen patients were treated for lower extremity ischemia and 14 for (a)-symptomatic stenosis in a peripheral bypass. Results of Duplex scanning were compared to the finding of PTA to assess the value of Duplex scanning done prior to PTA. Duplex scanning showed 51 lesions eligible for PTA, in 48 of 51 lesions (94%) the location as found with Duplex scanning was in agreement with the findings of the angiogram during PTA. Of a total of 31 patients scheduled for PTA, Duplex scanning predicted the indication for PTA adequately in 26 patients (84%). No complications were seen. Duplex scanning proved to be a valuable tool in the detection of lesions suitable for PTA. Furthermore, puncture site and route can be determined by means of Duplex scanning.