At our department, the routine treatment of deep venous thrombosis is low molecular weight heparin (Fragmin) in doses of 80-120 anti-Xa Units/Kg body weight/12h subcutaneously. In an open study we found that anti-thrombotic efficacy of the treatment, and safety with regard to bleeding, was the same as found in controlled studies. The patient population was characterized by old age and high morbidity. Nevertheless, eight out of 30 patients (26%) could be transferred to ambulant care on day 2-4. We conclude that low molecular weight heparin facilitates out-patient care of uncomplicated cases of deep venous thrombosis.