This project examines the impact of physician employment and consolidation on spending. Specifically, it will assess the impact of physician management companies (PMCs) that employ anesthesiologists on prices, surprise billing, upcoding, and total spending across hospital inpatient and outpatient facilities and ambulatory surgery centers (ASCs). The project also will consider if outcomes differ between private equity-backed PMCs and those without private equity funding. The analysis will use commercial claims data from the Health Care Cost Institute for years 2011 to 2017 and focus on PMCs that contract with hospitals and ASCs to staff their anesthesia departments. They also will use corporate filing data, mergers and acquisitions data, and Medicare Data on Provider Practice and Specialty to build a panel dataset that identifies whether anesthesiologists staffing a facility are employed by a PMC.