OBJECTIVE To compare robotic-assisted laparoscopy with conventional laparoscopy for treatment of advanced stage endometriosis insofar as operative time, estimated blood loss, complication rate, and length of hospital stay. METHODS Retrospective cohort study (Canadian Task Force classification II2). All procedures were performed by one surgeon between January 2004 and July 2012. Data was collected via chart review. METHODS Tertiary referral center for treatment of endometriosis. METHODS Four hundred twenty women with advanced endometriosis. METHODS Fertility-sparing surgery to treat advanced endometriosis, either via conventional or robotic-assisted laparoscopy. RESULTS Patient demographic data, operative time, estimated blood loss, complication rate, and length of hospital stay were compared between the 2 groups. Two hundred seventy-three patients underwent conventional laparoscopy and 147 patients underwent robotic-assisted laparoscopy for fertility-sparing treatment of advanced stage endometriosis. Patients in both groups had similar characteristics insofar as age, body mass index, and previous abdominal surgeries. There were no significant differences in blood loss or complication rate between the 2 groups. Mean operative time in the conventional laparoscopy group was 135 minutes (range, 115-156 minutes), and in the robotic-assisted laparoscopy group was 196 minutes (range, 185-209 minutes), with a mean difference in operative time of 61 minutes (p < .001). Length of hospital stay was also significantly increased in the robotic-assisted laparoscopy group. Most patients who underwent conventional laparoscopy were discharged to home on the day of surgery. Of 273 patients in the conventional laparoscopy group, only 63 remained in the hospital overnight, and all 147 patients in the robotic-assisted laparoscopy group were discharged on postoperative day 1. CONCLUSIONS Conventional laparoscopy and robotic-assisted laparoscopy are excellent methods for treatment of advanced stages of endometriosis. However, use of the robotic platform may increase operative time and might also be associated with longer hospital stay.