Peter Littlewood came to Chicago from Cambridge University, United Kingdom, where he was head of the Cavendish Laboratory and the Department of Physics at the University of Cambridge. He previously headed the Theory of Condensed Matter Group at the Cavendish Laboratory. During a 2003–2004 sabbatical leave, he was Matthias Scholar at Los Alamos National Laboratory.
Prior to joining Cambridge, he worked at Bell Laboratories from 1980 to 1997, finishing his time there as head of Theoretical Physics Research.
He holds a bachelor's degree in natural sciences (physics) and a PhD in physics, both from the University of Cambridge. He is a fellow of the Royal Society of London, the Institute of Physics, the American Physical Society, and an associate member of the World Academy of Sciences (TWAS).