ABSTRACT THE IMPACT OF OPT-OUT LEGISLATION ON ACCESS AND DELIVERY OF ANESTHESIA SERVICES IN CALIFORNIA Anesthesia services provide the support and stability for patient safety during surgical procedures. The service delivery can come from a variety of providers trained in anesthesia, and the typical approach comes in a team model of physician anesthesiologist (MDA), supervising a certified registered nurse anesthetist (CRNA). Researchers examine the various anesthesia services consisting of MDA alone, CRNA only, and the anesthesia care team model (ACT) with focus on their safety and quality. Stakeholders debate which anesthesia method of delivery is best suited for the patient care. In recent literature, these methods were tested by focusing on variables, including the anesthesia practitioner type and their skill sets, patient complexity, and defined patient outcomes, such as pain management, postoperative nausea and vomiting, length of hospitalization, and death. In 2001, the Executive Branch of the United States (U.S.) Federal Government released a rule, Medicare and Medicaid Programs; Hospital Conditions of Participation: Anesthesia Services, allowing states to opt-out of the federal requirement stipulating that a physician must supervise the delivery of anesthesia care by a CRNA to provide greater access to services when shortages of providers exists (Centers for Medicare and Medicaid Services, 2001; Lewis, Nicholson, Smith, & Alderson, 2014; & Sun, Miller, & Halzack, 2016). President Clinton signed that conditions of participation enacting the rule nationwide. However, his successor President Bush, amended this ruling to become state specific. This requirement intended to support access to care in rural areas improve. Since 2001, nineteen states have passed opt-out legislation; for example, California was the 15th state to opt out in 2009 (Sun et al., 2016). However, few studies to date include investigation of how this legislation affected the access to quality anesthesia care. The purpose of this proposed study is to analyze how opt-out legislation in California has impacted the three types of anesthesia delivery methods with nurse anesthesia practice for surgical services and their subsequent outcomes.