In 1960 he received a LL.D. again from City College, followed by a D.Sc. at the University of Rochester in 1962. He became Professor and Executive Head of the Department of Biochemistry, Stanford University, in 1959. In an interview in 1997, Arthur Kornberg (referring to Josh Lederberg) said: "Lederberg really wanted to join my department. I knew him; he's a genius, but he'd be unable to focus and to operate within a small family group like ours, and so, I was instrumental in establishing a department of genetics [at Stanford] of which he would be chairman."