The prevalence of venous leg ulcers is as high as 1% to 1.5%, and the total costs of this disease are 1% of the total annual health care budget in Western European countries. Treatment modalities are conservative or surgical. Subfascial endoscopic perforating vein surgery (SEPS) combined with superficial vein ligation is performed in many centers to address vein incompetence in patients with chronic venous leg ulcers. Several reports describe good healing and low recurrence rates, although a randomized trial to compare surgical treatment including SEPS and treatment of the superficial venous system to conservative modalities has never been performed. Therefore, a prospective, randomized, multicenter trial was conducted to study whether ambulatory compression therapy with venous surgery is a better treatment than just ambulatory compression therapy in venous leg ulcer patients. Patients with an active (open) venous leg ulcer (CEAP C6) qualified for the study. The study consisted of two treatment groups. All patients were treated by standardized ambulatory compression therapy, and half of the patients received SEPS. Concomitant superficial venous incompetence was also treated in the second group. For allocation to both treatment groups, each patient was assigned by a computer program at the randomization center. The primary goal of the study was to compare the ulcer-free period during follow-up in both study groups. Secondary end points were ulcer healing and recurrence rates. From April 1997 until January 2001, 200 ulcerated legs (170 patients) were included in the study in 12 centers in The Netherlands. A total of 97 ulcers were allocated to the surgical group and 103 to the conservative group. Patient characteristics were similar in the two treatment groups at baseline, with the exception of a higher proportion in the conservative group of diabetes mellitus. Healing rates were 83% in the surgical group and 73% in the conservative group (not significant; median time to healing, 27 months). Recurrence rates were the same in both treatment groups (22% surgical vs 23% conservative). During follow-up of a mean of 29 months (median, 27 months) in the surgical group and 26 months (median, 24 months) in the conservative group, we found that in the surgical group, the ulcer-free rate was 72%, whereas in the conservative group this rate was 53% (P = .11; Mann-Whitney test). Patients with recurrent ulceration or medially located ulcers in the surgical group had a longer ulcer-free period than those treated in the conservative group (P = .02 for both). A first-time ulcer and one of the centers also had a positive effect on the ulcer-free period during follow-up (P < .001 and P = .02), independent of the treatment group. Deep vein incompetence did not affect the ulcer-free period. In conclusion, we suggest that patients with medial and/or recurrent ulceration should receive surgery combined with ambulatory compression therapy. A dedicated center should provide care for those patients.