As a Massachusetts Institute of Technology faculty member he sponsored easier access to computer facilities at MIT during the early development of the subculture.

Dennis was also a member of the Tech Model Railroad Club, which incubated much of the early slang and traditions of hacking.

[5] After completing his doctorate, Dennis became part of the MIT's Department of Electrical Engineering and Computer Science's faculty, being promoted to full professor in 1969.

Along with his students, Dennis adopted the concepts of single assignment and dataflow, in which instructions are executed as soon as data are available (this specific model is called "static" in contrast to Arvind's "dynamic").

[6] In 2009, Dennis was elected a member of the National Academy of Engineering for contributions to sharing and protection in computer systems and parallel architectures based on data flow principles.