<h3>Study Objective</h3> Evaluate the intraoperative visual detection of endometriosis compared to final histopathologic diagnosis based on lesion type. <h3>Design</h3> Prospective clinical study. <h3>Setting</h3> Tertiary-care, academic medical center. <h3>Patients or Participants</h3> Seventy-seven patients underwent surgical evaluation for suspected endometriosis by high-volume endometriosis surgeons. <h3>Interventions</h3> Minimally invasive complete pelvic peritonectomy with documentation of visual presence or absence of endometriosis and lesion type. Powder burn lesions were defined as typical lesions. White scarring, clear vesicles, red flame, and peritoneal pockets were defined as atypical lesions. <h3>Measurements and Main Results</h3> A total of 1,069 peritoneal specimens were obtained with visual detection of endometriosis reported for 352 specimens (32.93%). Endometriosis was confirmed on histopathologic evaluation in 65.8% powder burn lesions, 51.6% white scarring, 45.7% clear vesicles, 39.1% red flame, and 28.9% peritoneal pockets (p=0.003). Additionally, 11.3% of specimens with no visible endometriosis demonstrated a positive histopathologic diagnosis. Overall sensitivity was 68.36%, specificity was 78.15%, positive predictive value was 49.72%, and negative predictive value was 88.66% for visual detection of endometriosis. White scarring was the lesion type with the highest sensitivity at 44.14% while the lowest sensitivity was for red flame lesions at 10.0%. All lesion types had a high specificity (powder burn 96.20%, white scarring 91.34%, clear vesicles 92.54%, red flame 97.84%, peritoneal pocket 95.91%). The positive predictive value varied depending on lesion type (powder burn 65.75%, white scarring 51.61 %, clear vesicles 45.74%, red flame 39.13%, peritoneal pocket 28.95%). <h3>Conclusion</h3> There is poor reliability for the visual detection of endometriosis at the time of surgical evaluation for endometriosis. Typical and atypical lesions have similar sensitivity, specificity, and positive predictive value for accurate visual detection of endometriosis. Specimens with no visible endometriosis are found to have histopathologic disease in 11.3% of specimens. This potential for atypical appearance and disease not macroscopically visible suggests a role for complete pelvic peritonectomy.