The need for unplanned anterior vitrectomy is an unanticipated event that can decrease the probability of good postoperative visual acuity, and generally result in worse long-term outcome after cataract surgery. Because cataract surgery is the most common surgery performed in ASCs, with millions being performed every year, even low unplanned anterior vitrectomy rates translate to relatively high total numbers of affected patients. ASCs can help keep rates low by tracking and comparing rates to established benchmarks, and facilitating mentoring as needed.