Overlapping surgery is the practice of surgeons scheduling distinct procedures on different patients concurrently. This practice has raised safety concerns. This large population-based retrospective study examined outcomes for nonoverlapping versus overlapping hip surgeries across Ontario, Canada. After adjustment for factors known to predict surgical outcomes, such as hospital and surgeon case volume and the patient's overall health, researchers found an association between increasing duration of surgical overlap and higher risk of complications. These results contrast with a recent single-center study that found no safety differences between overlapping and nonoverlapping neurosurgeries. An accompanying editorial acknowledges the mixed results of safety studies for overlapping surgeries and calls for large, multicenter, prospective studies across a range of surgical procedures with long-term follow-up.