John M. Vlissides, 44, a researcher for IBM who revolutionized the field of software development, died Nov. 24 of a brain tumor at his home in Mohegan Lake, N.Y.
Dr. Vlissides's area of expertise, object-oriented software design, was a computer programming paradigm based on the idea that a program is composed of a collection of individual units, or objects, rather than a list of instructions to the computer. The objects mimic the objects in the real world with which the program is concerned. He believed it was a more flexible approach than traditional programming paradigms.
Best known for his role in creating the field of software patterns, he was one of four authors of "Design Patterns" (1994), the seminal work on the topic. Known in the world of computer research as "The Gang of Four," Dr. Vlissides and his colleagues provided a standard vocabulary for talking about problems of software design. Before they devised the vocabulary, the object-oriented experience "could not be known or knowable," Dr. Vlissides often said.
Their work continues to influence all modern software systems, and their book, 11 years after publication, remains a computer science bestseller. Dr. Vlissides also was a mentor to younger computer scientists writing about object-oriented software design.
John Matthew Vlissides was born in the District and grew up in McLean, where he graduated with honors from Langley High School in 1979. He received a bachelor's degree from the University of Virginia in 1983, a master's degree from Stanford University in 1985 and a doctorate from Stanford in 1990. All of his degrees were in electrical engineering.
As a graduate student and post-doctoral scholar at Stanford, he co-developed InterViews, a set of libraries and tools for developing graphical applications. He also served as a consultant to Hewlett-Packard Co., Fujitsu America Inc. and several other companies.
He joined IBM in 1991, working as a research staff member at the company's T.J. Watson Research Center in Hawthorne, N.Y. He conducted research in user interface development tools, programming environments and object-oriented system architecture, programming and visualization. He continued to provide consulting services to companies, laboratories, universities and government agencies around the world.
His honors included the electrical engineering department Chairperson's Prize at the University of Virginia in 1983, the IBM Outstanding Technical Achievement Award in 1996 and election to the IBM Academy of Technology in 1998.
An infant daughter, Helen Vlissides, died in 1997.
Survivors include his wife of 13 years, Dru Ann Vlissides of Mohegan Lake; three children, Matthew, Mark and Robert Vlissides of Mohegan Lake; his parents, Matthew Vlissides Sr. and Sophia Vlissides of McLean; a sister, Irene Vlissides Levy of Falls Church; and two brothers, Nicholas Vlissides of Fairfax City and Matthew Vlissides Jr. of Arlington.