Dr. Sai-Hong Ignatius Ou completed his M.D. and Ph.D. degrees at the University of Texas Southwestern Medical Center in Dallas, Texas; his internal medicine residency training at Duke University Medical Center, Durham, North Carolina; and his hematology-oncology fellowship training at Beth Israel Deaconess Medical Center, Harvard Medical School in Boston, Massachusetts. Dr. Ou is board-certified in internal medicine and medical oncology by the American Board of Internal Medicine. Dr. Ou joined the University of California Irvine School of Medicine immediately after completing his fellowship as an assistant clinical professor of medicine in 2003 and has been promoted to health science clinical professor of medicine in 2015. He has published about 110 peer-reviewed manuscripts in journals including New England Journal of Medicine, Lancet Oncology, Journal of Clinical Oncology, Cancer Discovery, Nature Medicine and JAMA Oncology, primarily in the field in targeted therapy in lung cancer including resistance mechanisms and the prognostic and predictive significance of smoking status and ethnicity in the outcome of lung cancer. In particular, Dr. Ou is one of the seven original principal investigators for the still ongoing phase I crizotinib trial that has led to the approval of crizotinib for the treatment of anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). Recently, the activity of crizotinib in ROS1-rearranged NSCLC has been reported in New England Journal of Medicine in which Dr. Ou is co-first author. Currently, Dr. Ou is involved in many early phase clinical trials involving novel and second-generation tyrosine kinase inhibitors in NSCLC driven by receptor tyrosine kinase rearrangement or mutations including as the lead author of of a global phase 2 study of a second generation ALK inhibitor, alectinib. Dr. Ou is also involved in the clinical trial of immunotherapy in numerous tumor types including squamous and non-squamous NSCLC. Dr. Ou is on the editorial board of Critical Reviews in Oncology/Hematology, Annals of Oncology, Clinical Lung Cancer, and Translational Lung Cancer Research. Dr. Ou is a scientific program committee member for the metastatic NSCLC track for the American Society of Clinical Oncology (ASCO) annual meeting from 2016 to 2018. Finally, Dr. Ou has been voted as one of America’s Best Doctors five years in a row since 2009.