While in college in 1950, Anderson first became interested in computers while taking programming courses for the Illiac I computer, which was under construction at the time. These courses were taught at Illinois by legendary computer scientist David Wheeler of Cambridge University. That same year Anderson married Lois Jean Kahl, whom he met in junior high school.

After leaving Illinois two years later, Anderson joined the MIT Lincoln Laboratory in Cambridge, Massachusetts. After a few years, he co-founded Digital Equipment Corporation (DEC) with Ken Olsen, who had been his first boss at Lincoln Labs. Digital at its peak was the second largest computer company in the world.

Early on, Anderson was active in professional societies and was General Chairman of the Eastern Joint Computer Conference in 1966, the largest professional meeting and exhibition of computer technology at the time.

He served as Director of Technology for Time, Inc. and spearheaded their evaluation of the future of the printed word during the explosion of television, long before the Internet existed.

With personal assets, he helped provide early stage financing for over twenty small technology companies. He was a trustee of Rensselaer Polytechnic Institute for sixteen years and provided endowment funding for the Lois J. and Harlan E. Anderson Center for Innovation in Undergraduate Education there.

He is a member of the Board of Advisors of the College of Engineering at the University of Illinois where he has provided endowment funding for the Lois J. and Harlan E. Anderson Laboratory for Global Education in Engineering. He has been a trustee of the Boston Symphony Orchestra for twelve years. A recent interest has been the study of the World War II work at Bletchley Park in England where the German Enigma code was broken.

The Andersons reside in New Canaan, Connecticut and have three children Brian, Gregory and Susan.

Anderson holds B.S. (1951) and M.S. (1952) degrees in physics from the University of Illinois.