Baily became a Putnam Fellow in 1952.[4] He studied at the Massachusetts Institute of Technology (MIT), receiving a Bachelor of Science in Mathematics in 1952, after which he attended Princeton University, receiving a Masters in 1953 and a Ph.D. in Mathematics in 1955 under the direction of his thesis advisor Kunihiko Kodaira (On the Quotient of a Complex Analytic Manifold by a Discontinuous Group of Complex Analytic Self-Homomorphisms).[5] Subsequently, he was an instructor at Princeton and then MIT. In 1957 he worked as a mathematician at Bell Laboratories. In 1957, he was appointed Assistant Professor and subsequently promoted to Professor in 1963 at the University of Chicago.