He served in the United States Navy during World War II, joining the faculty of Harvard Business School in 1947 and becoming a tenured professor in 1956.

[1][2][3] Following his graduation from Harvard Business School, Williams worked in the loan department at Manufacturers Trust Company in New York City for two years.

[2] Prior to this experience, Williams was an avowed pacifist, but after visiting Nazi Germany he felt obligated to enlist in the United States Navy.

[2][3] Following the completion of his initial training, Williams was assigned to the aircraft carrier USS Lexington (CV-2), where he served as a dispersing officer (or paymaster) for a 2,000-person crew.

[2][3] During the evacuation of the Lexington, Williams swung from a line onto the deck of an American destroyer that had arrived to rescue the crew of the sinking aircraft carrier.

[2][3] Post-rescue, Williams was assigned to shore duty and served as an instructor at the Navy Supply Corps School at Harvard University.

[2] After a year of teaching at the University of Michigan, Williams was discharged from the United States Navy with the military rank of lieutenant commander in 1947.

[2][3][9] While teaching at Harvard Business School, Williams earned his doctorate in commercial science in 1951 and was promoted to associate professor.

[1][2] Following his retirement, Williams was Harvard Business School's George Gund Professor of Commercial Banking Emeritus until his death in 2011.

[2] Williams utilized the case study method of teaching, using real life examples to facilitate discussion among his students.

[12] Two years later, he co-authored the textbook Case Problems in Finance with Harvard Business School colleague Pearson Hunt.

[14][15][16] Williams' notable former students include John S. R. Shad, chairman of the U.S. Securities and Exchange Commission; Thomas C. Theobald, chairman and chief executive officer of Continental Bank Corporation; Clemmie Spangler, President of the University of North Carolina; and John H. McArthur, Dean Emeritus of Harvard Business School.

He also taught in locally sponsored programs in Italy, Japan, Mexico, the Netherlands, the Philippines, the United Kingdom, and Venezuela.

Sessions of the Senior Bank Officers Seminar were held at Harvard Business School for many years and were attended by approximately 2,300 executives.

[10] Following his death, a plaque in Williams' honor was installed at Harvard Business School, with the following inscription: "Extraordinary teacher, inspiration to generations of students who have put his percepts into practice".

John H. McArthur, Dean Emeritus of Harvard Business School, said: "as a teacher, researcher, author, wise counsel, and good friend, Charlie Williams has had an enormous impact over the years on all of us at HBS as well as upon the entire banking industry."