OBJECTIVE: To compare two contact and non-contact techniques using the VLAP system (visual laser ablation of the prostate). PATIENTS AND METHOD: From January 1994 to April 1995, two groups of 50 patients were included in a randomized prospective study and were treated by the contact and non-contact laser technique, respectively. These patients presented with symptomatic BPH requiring transurethral electroresection. These patients were evaluated according to subjective (AUA score) and objective criteria (maximum flow rate, transrectal and suprapubic ultrasonography). ND:YAG laser energy was delivered by a Medilas 4100 source via a lateral beam fibre. Objective success criteria were an improvement of the AUA score by at least 50% and of the maximum flow rate by at least 50% with a difference of 4 mL/s. The failure criterion was the need to perform complementary electroresection during the first 6 postoperative months. RESULTS: the mortality was 2% (cardiovascular causes), and the overall morbidity (first postoperative month) was 29%, with 21% of a vesical irritation syndrome, 6% of urinary tract infection and 2% of bladder clots. The global result at 12 months showed a statistically significant postoperative improvement of the subjective and objective parameters studied preoperatively (p=0.0001). In the contact group, the AUA score, mean maximum flow rate and residual urine, which had preoperative values of 19.1, 9.1 mL/s and 141 mL, respectively, were equal to 2.3, 15.6 mL/s and 45 mL at 12 months. In the non-contact group, the same parameters, which had preoperative values of 17.8, 9.2 mL/s and 87 mL, respectively, were equal to 3.8, 13.3 mL/s and 47 mL at 12 months. The results, evaluated as a function of objective success criteria, showed a 12-month success rate of 68% for the contact method and 61% for the non-contact method. The mean hospital stay was 6 days and the mean duration of bladder catheterization was 5 days with the two techniques. During follow-up, 7% of patients required revision by electroresection, regardless of the technique used. CONCLUSION: this study demonstrated identical results for the contact and non-contact techniques using the VLAP system.