Chronic complete occlusions still represent the major technical limitation of percutaneous transluminal balloon angioplasty, both in peripheral and coronary vessels. The clinical use of low speed rotational angioplasty (ROTACS) started in 1986 for the peripheral and in 1987 for the coronary vessels, and has already become part of the clinical routine in several centers. Up to now, more than 300 patients with peripheral and more than 200 patients with coronary occlusions were treated in Frankfurt. In peripheral occlusions the acute success rate was more than 80% if used as the first attempt; after failure of conventional techniques still more than 60% of the vessels could be recanalized successfully. In addition to occlusions of the arteries of the lower limbs, the indication now includes the iliac artery and several other indications are under investigation. In each of the patients with chronic coronary occlusions an attempt with conventional techniques had failed before. Following a learning curve, which was also influenced by a better understanding of morphological preconditions, the acute success rate has now reached 70%. Both in patients with peripheral and those with coronary occlusions no deaths occurred. First angiographically documented long-term results in both indications are comparable to conventional balloon angioplasty. It is concluded that the use of low speed rotational angioplasty (ROTACS) can improve the results of nonoperative invasive treatment, both in peripheral and in coronary arteries.