author of the book Decline and Fall of the American Programmer. Yourdon Inc. In 1974, Yourdon founded the consulting firm Yourdon Inc. in New York, which provided consulting, educational and publishing in the field of software engineering. In the early 1980s, the company had multiple offices in North America and Europe and a staff of 150 people. They trained over 250,000 people in the topics of structured programming, structured design, structured analysis, logical data modeling and project management. In 1986, Yourdon sold the consulting company. It later became part of the Canadian (Québec) software company CGI Informatique. The publishing division had published over 150 books on software engineering topics before it became part of Prentice Hall. Yourdon structured method In the 1980s Yourdon developed the Yourdon structured method (YSM) in SSADM based on the functional structuring. The method supports two distinct design phases: analysis and design. YSM includes three discrete steps: the feasibility study; essential modeling; and implementation modeling. It offers a series of models: The behavioral model: states that system behavior can be described in three ways: functions, dynamics and relationships. The processor environment model (PEM): describes the allocation of computing functions in processor hardware. The software environment model (SEM): defines the software architecture and its effects from each processor. The code organizational model (COM): shows the modular structure of each task The Yourdon structured method (YSM) and structured analysis and design technique (SADT) are examples of structured design methods. Year 2000 (Y2K) problem During the late 1990s, he was one of the leading proponents of the theory that the 'Y2K bug' could lead to a collapse of civilization, or at least protracted economic depression and technological breakdown on a wide scale. He wrote several books on the subject, including Time Bomb 2000 (), and produced at least one video putting forth that theory (and offering advice on how to survive the coming crisis). Yourdon was criticized by some when his predictions (vigorously refuted by some experts in advance) failed to materialize at the scale predicted. This may have caused him to lose credibility with some in the software industry. Final years and death 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. He died on January 20, 2016, as a result of a post-surgical blood infection. Personal life Yourdon was married