Thoughtful and easy to read, Odyssey of a Physician-Scientist is a fascinating journey that, in capturing the essence of the man, also encapsulates the heart of what it means to be a physician and a scientist. John Ross Jr., MD, is a Distinguished Professor of Medicine emeritus at the University of California San Diego School of Medicine. A graduate of Dartmouth College and the Cornell Medical College, Ross received clinical and research training at the Johns Hopkins Hospital, the Columbia-Presbyterian Medical Center and the New York Hospital-Weill Cornell Medical Center. Among his many accomplishments was his development of transseptal left heart catheterization in 1958, now widely used in cardiac diagnosis and treatment. When Dr. Ross accomplished this at the National Heart Institute in Bethesda. Dr. Eugene Braunwald, who headed the institute, said "One of the most thrilling events in my professional life occurred in 1959 when I observed Ross carry out the first transseptal puncture from the right atrium into the left atrium, and that this occurred in the Heart Institute's Catheterization Laboratory- Ross, Glenn Morrow (the Chief of Cardiac Surgery) and I knew that something very important had just occurred".