 The aim of the study is to compare PTFE-graft bypass surgery versus Viabahn endoprosthesis for femoropopliteal arterial occlusion in intermittent claudication and critical ischaemia in patients who would be technically amenable for both treatments. The primary objective is to compare primary patencies of the two treatments. The secondary objective of the study is to evaluate secondary patency, functional status, the quality of life and costs of the new endovascular therapy. 