Lysis of deep venous thrombotic obstruction in the extremities has been shown to decrease the frequency and severity of symptoms of postthrombotic syndrome. However, for those lesions that contain organized thrombus, the use of conventional methods to lyse thrombus is less successful than for acute thrombus. The authors here present a novel method for treatment of older, organized thrombus using excimer laser. This technique can obviate some of the limitations of the other methods and allow effective treatment when other methods fail. It has been used successfully in 19 patients with excellent results and is recommended for those cases.