Superficial venous thrombosis (SVT) of the lower extremities is a common ailment seen in outpatient offices of vascular medicine and surgery practices. This study of 60 consecutive outpatients was carried out to examine the incidence of concomitant deep venous thrombosis (DVT), risk factors associated with SVT, recurrence of SVT and/or new DVT, and the role of anticoagulant therapy in the prevention of recurrence. Concomitant SVT and DVT (13%) were significantly less likely to be present in patients with varicose veins as compared to patients without varicose veins (p < 0.04) and more likely to be present in patients with a previous history of DVT (p < 0.02). Fifteen patients (25%) developed either recurrent SVT or new DVT, with two patients developing both SVT and DVT. The absence of varicose veins and the presence of a hypercoagulable condition (n = 12) appeared to influence the development of new DVT but not the recurrence of SVT. Recurrent SVT was much more likely in patients with thrombosis of the tributaries (p < 0.0008). New DVT was seen significantly less frequently in patients on anticoagulants (p < 0.02).