Edward Claire Gurski, 56, chairman of the Fairfax County Planning Commission since 1975 and an economist with the CIA since the early 1950s, died of cancer Monday at Fairfax Hospital. He was a resident of Springfield.

The planning commission is an 11-member citizen group that makes recommendations on rezoning applications and other planning matters before they are sent to the County Board of Supervisors for final decision. While the commission is largely advisory, it plays a major role in shaping the rapidly growing county.

Mr. Gurski had been a member of the planning commission since 1971 and was a community leader in Springfield before that. After becoming commission chairman, he pledged to maintain a high degree of professionalism. The commission's executive director, James C. Wyckoff Jr., recalled Mr. Gurski saying shortly after becoming chairman, "We're going to make this the best darn planning commission in the country." A year later, Wyckoff recalled, Mr. Gurski told him, "Well, we did it."

Though the commission was often embroiled in tough cases involving suburban growth, Mr. Gurski had a reputation for fairness and making certain everyone had a say.

Edgar A. Prichard, a longtime zoning attorney in Fairfax, said Mr. Gurski "had an unlimited amount of patience. He was scrupulously fair in all his dealings with the public and attorneys."

He was a native of Jamestown, N.D. He served with the Army in the Pacific during World War II. Following the war, he moved to this area and received a bachelor's and a master's degree in economics from Georgetown University.

He was a past president and life member of the Virginia Citizen Planners Association. In 1976 he received that organization's Planner of the Year Award. He also was a member of the American Planning Association.

His first marriage, to Marie Gurski, ended in divorce.

Survivors include his wife, Dorothy, of Springfield; four sons by his first marriage, Edward T., of Culpeper, and John, Paul and William, all of Fort Collins, Col.; a stepson, Andy Trimpin of Springfield; a stepdaughter, Kathy Dalby of Honolulu, Hawaii, and two sisters, Mary Gulmon of Valley City, N.D., and Margaret Cadieux of Chicago.

The family suggests that expressions of sympathy be in the form of contributions to the charity of one's choice.