Objective: To evaluate adhesion reformation after laparoscopic excision of endometriosis and adhesiolysis in women with chronic pelvic pain. Design: Prospective clinical trial. Setting: University hospital. Patient(s): Thirty-eight women with endometriosis and chronic pelvic pain. Intervention(s): A primary and second-look laparoscopy with adhesiolysis and excision of endometriotic lesions with a neodymium-yttrium argon garnet surgical laser technologies (SLT) contact laser. Main Outcome Measure(s): Adhesion formation and character (thin, thin and thick, or thick). Location of adhesions at a first laparoscopy was compared with de novo or reformation of adhesions and the location of adhesions at a second surgery. Result(s): Adhesions or adhesions combined with endometriotic lesions were significantly more likely to reform at second surgery compared with sites having only an endometriosis lesion. Thick adhesions were associated with a significantly increased likelihood of an adhesion reforming, compared with thin adhesions or thin and thick adhesions. Lesions or adhesions involving the ovarywere more likely to be associated with adhesions at a subsequent surgery, compared with lesions in the adjacent ovarian fossa or fallopian tube. Conclusion(s): Most patients developed adhesions after radical surgical excision of endometriosis for pelvic pain. The high incidence of adhesion formation after surgery for endometriosis underscores the importance of optimizing surgical techniques to potentially reduce adhesion formation. Objective: To evaluate adhesion reformation after laparoscopic excision of endometriosis and adhesiolysis in women with chronic pelvic pain. Design: Prospective clinical trial. Setting: University hospital. Patient (s): Thirty-eight women with endometriosis and chronic pelvic pain. Intervention (s ): A primary and second-look laparoscopy with adhesiolysis and excision of endometriotic lesions with a neodymium-yttrium argon garnet surgical laser technologies (SLT) contact laser. Main Outcome Measure (s): Adhesion formation and character (thin, thin and thick, or thick). Location of adhesions at a first laparoscopy was compared with de novo or reformation of adhesions and the location of adhesions at a second surgery. Result (s): Adhesions or adhesions combined with endometriotic lesions were significantly more likely to reform at second surgery compared with sites having only an endometriosis lesion. Thick adhesions were associated with a significantly increased likelihood of an adhesion ref orming, compared with thin adhesions or thin and thick adhesions. Lesions or adhesions involving the ovarywere more likely to be associated with adhesions at a subsequent surgery, compared with lesions in the adjacent ovarian fossa or fallopian tube. Conclusion (s): Most patients developed adhesions after radical surgical excision of endometriosis for pelvic pain. The high incidence of adhesion formation after surgery for endometriosis underscores the importance of optimizing surgical techniques to potentially reduce adhesion formation.