He took a job with Bell Telephone Laboratories and worked there from 1950 to 1970, eventually becoming executive director for communications research.
He founded consulting group EED, Inc. in 1977, advising industry, government, and universities on technology, research, and innovation management.
David was also active in public service to his adopted state, serving on the board of the New Jersey Commission on Science and Technology (NJCST)[8] alongside William O. Baker, his former vice president at Bell Labs.
[9] Once the NJCST became a statutory agency with responsibility for the state's programs in science & technology-based economic development in 1985, David was re-appointed to its board and served as chair of its budget committee.
[11] In 2012, David was a co-signatory of an op-ed in The Wall Street Journal questioning the scientific consensus on global warming.