The thread of continuity through all Simon's work has been his interest in human decision-making and problem-solving processes, and the implications of these processes for social institutions.
 

In 1949, he joined Carnegie Mellon University as a Professor of Computer Science and Psychology, and a member also of the Departments of Philosophy and of Social and Decision Sciences, and the Graduate School of Industrial Administration.

In 1978, he received the Alfred Nobel Memorial Prize in Economic Sciences, and in 1986 the National Medal of Science; in 1969, the Distinguished Scientific Contribution Award of the American Psychological Association, in 1975 the A.M. Turing Award of the Association for Computing Machinery (with Allen Newell), in 1988, the John von Neumann Theory Prize of ORSA/TIMS, and in 1995, the Research Excellence Award of the International Joint Conference on Artificial Intelligence.