Dr. Isidore Cohn, Jr., whose premier research established him as the preeminent expert in the role of antibiotics in surgery of the gastrointestinal tract, served as the Chair of the Department of Surgery, LSU School of Medicine (New Orleans) from 1962-1989. During his tenure, one of the longest in the history of American surgery, Dr. Cohn transformed the department from one staffed by part-time faculty, devoid of a meaningful research program, into one of national and academic prominence. He trained over 300 surgeons and introduced creative changes into the residency program, including affiliation agreements of great benefit to the university and associated private hospitals. The author, selected as Dr. Cohn’s first Chief Resident in 1962, enjoyed a 60-year relationship with Dr. Cohn that followed an arc from student to research assistant and co-author, faculty associate, and ultimately to colleague and family friend. Dr. Cotlar’s biography of Cohn includes the evolution of the LSU surgery department since the school’s inception in 1931, from a unique perspective which recognizes the extraordinary contributions of many who participated in his training and subsequently formed the core of the surgery department under the leadership of his mentor.