Weissman was born in the Bronx on July 12, 1919. After graduating from Townsend Harris High School, he studied business at the City College of New York (whose business school became Baruch College), edited a small weekly newspaper in New Jersey and then became a reporter for The Star-Ledger of Newark, New Jersey. The day after the Japanese Attack on Pearl Harbor, he enlisted in the United States Navy and, during World War II, served for more than three years as a submarine destroyer commander and on an anti-personnel naval ship. Following military service, he made a career change to public relations, first working at Samuel Goldwyn Productions and later becoming a public relations consultant at Benjamin Sonnenberg, where Philip Morris was a client.
In 1952, Weissman joined Philip Morris as assistant to the president and director of public relations. The next year, he was elected vice-president of the company, handling not only public relations and market research, but also new product development and packaging. He joined the board of directors in 1958 and went on to become chairman of the board and chief executive officer of Philip Morris International, leading its expansion overseas. He was appointed president of the corporation in 1967, vice-chairman in 1973 and chairman and chief executive officer in 1978.
Weissman retired in 1984, but continued to serve the company in various advisory roles. He also joined the board of directors of Gulf+Western, which later became Paramount Communications, a position he held for the next decade.
His marketing inspiration came from William K. Howell, who is credited with the success of Marlboro cigarettes and the Miller Brewing Company. Howell and Weissman introduced the Marlboro Man, an advertising figure who help propel Philip Morris to a leading position in the tobacco industry.
Weissman's volunteer pursuits included serving as board chairman of the Lincoln Center for the Performing Arts, founding board member of Jazz at Lincoln Center, a trustee of the Whitney Museum, and a director of the New York Chamber of Commerce and Industry. His political work landed him on the master list of Nixon political opponents.
Civil rights activist (CCRI)
In December, 1958 Weissman - pen name George Lavan - became a founding member and secretary of New-York-based The Committee to Combat Racial Injustice (CCRI) along with NAACP's Robert F. Williams as Chairman, Conrad Lynn, New York attorney active in civil rights cases, Reverend C. K. Steele of Tallahassee, Florida to work on behalf of nine-year-old James Hanover Thompson and seven-year-old David Simpson, the children falsely accused and jailed in the infamous Kissing Case in 1958. The CCRI's main activities on behalf of the boys which contributed to their release in early 1959, included "fund-raising, helping to secure legal counsel, and soliciting public and private moral support." "The committee's founders also included Dr. Albert E. Perry, L. E. Austin, editor of the Carolina Times, Conrad Lynn, New York attorney active in civil rights cases, Reverend C. K. Steele of Tallahassee, Florida.  Weissman published an account of the case in The Nation in January, 1959.
- Martin, Douglas. "George Weissman, Leader at Philip Morris and in the Arts in New York, Dies at 90 ", The New York Times, July 27, 2009. Accessed July 28, 2009.
- "Committee to Combat Racial Injustice Records, 1957-1965", University of Wisconsin Digital Collections
- George L. Weissman (January 17, 1959), The Kissing Case, The Nation, pp. 46–48
- Weissman, George (December 2, 1998). First Annual Weissman Lecture on the Influence of the Arts on Society.
- Corporate history via Altria