in astronomy from the California Institute of Technology (Caltech), and received a Ph.D. in computer science from MIT under Professor Jack Dennis.
In 1994, he joined Rational Software, where he worked with Ivar Jacobson and Grady Booch ("the Three Amigos") to develop Unified Modeling Language (UML).
Later they merged their software development methologies, OMT, OOSE and Booch into the Rational Unified Process (RUP).
[2] Rumbaugh's main research interests are formal description languages, "semantics of computation, tools for programming productivity, and applications using complex algorithms and data structures".
Rumbaugh has written a number of books about UML and RUP together with Ivar Jacobson and Grady Booch.