In 1964 Yourdon started working at Digital Equipment Corporation developing FORTRAN programs for the PDP-5 minicomputer and later assembler for the PDP-8.

[1] After he sold this firm in 1986 he served on the Board of multiple IT consultancy corporations and was advisor on several research project in the software industry throughout the 1990s.

In June 1997, Yourdon was inducted into the Computer Hall of Fame, along with such notables as Charles Babbage, James Martin, Grace Hopper, and Gerald Weinberg.

[3] In the late 1990s, Yourdon became the center of controversy over his beliefs that Y2K-related computer problems could result in severe software failures that would culminate in widespread social collapse.

[4] Due to the efforts of Yourdon and thousands of dedicated technologists, developers and project managers, these potential critical system failure points were successfully remediated, thus avoiding the problems Yourdon and others identified early enough to make a difference.

He wrote several books on the subject, including Time Bomb 2000 (ISBN 0-13-020519-2), and produced at least one video putting forth that theory (and offering advice on how to survive the coming crisis).

In his final years, Yourdon served as an internationally recognized expert witness and computer consultant specializing in project management, software engineering methodologies, and Web 2.0 development.