As Surgeon-in-Chief and Chair of Surgery, Dr. Ostlie is accountable for the Hospital's surgical services and leadership within all surgical divisions, including General Surgery, ENT, Dermatology, Urology, Congenital Heart Surgery, Orthopedics, Neurosurgery, Ophthalmology, Plastic Surgery, Gynecology, Trauma, Anesthesiology and Transplant.

Dr. Ostlie continues to have a special interest in chest wall abnormalities, performing his first minimally invasive repair in 2000 and more than 400 in his career. He has participated in research focusing on chest wall care including technical modifications, operative approaches, and postoperative pain management.

Dr. Ostlie also provides administrative and clinical leadership to four clinical program centers that encompass the surgical divisions, the critical care program, the neurosciences institute, and the heart center. He remains committed to education and research, and has administrative oversight for both the research and educational endeavors at Phoenix Children's Hospital.

Prior to joining Phoenix Children's Hospital, Dr. Ostlie served as Surgeon-in-Chief at American Family Children's Hospital in Madison, WI, and held Professor of Surgery and Professor of Pediatrics positions at University of Wisconsin School of Medicine and Public Health from 2012 through 2016. Dr. Ostlie completed his residency in general surgery at Mayo Clinic Arizona from 1995 to 2000, during which time he also spent one year as a research fellow at Cambridge University, Cambridge, UK. After general surgery residency, he completed his pediatric surgery fellowship and surgical critical care fellowship at Children's Mercy Hospital, Kansas City, MO. During his 12 years with the institution, he rose through numerous leadership roles including vice chair of the Department of Surgery and program director of both the Pediatric Surgery Residency and Surgical Critical Care Fellowship.

Dr. Ostlie remains clinically active with focused interest in chest wall abnormalities, esophageal disorders, minimally invasive surgery, and neonatal surgery. He continues his academic effort primarily in outcomes research. He has been instrumental in the establishment of two multi-institutional consortia focusing on the development of research to expand the knowledge surrounding rare pediatric surgical conditions. He has authored more than 215 peer-reviewed publications, 20 book chapters, and is the editor of two books. He has served as the Pediatric Editor of the Journal of Laparoendoscopic and Advanced Surgical Techniques and is the current Editor of Seminars in Pediatric Surgery.