Agnes Jacqueline Smith Gill, 45, cofounder and vice president of Gill Associates Inc., Washington management consultants, died of cancer Sunday at her Silver Spring home.

Born and reared in Washington, Mrs. Gill graduated from Dunbar High School and Howard University, where she earned a bachelor's degree in botany in 1956.

She subsequently lived in Binghamton, N.Y., and in Philadelphia, where she was a cancer researcher with the Agnes Barr Chase Institute at Temple University for about three years before returning to Washington in the early 1960s.

In 1970, after she and her husband, Dudley W. Gill Jr., founded Gill Associates, she served as vice president for corporate affairs, directing the firm's affirmative action and equal employment opportunity programs.

Mrs. Gill also was instrumental in establishing the boat manufacturing firm of Marine Craft America, a predecessor of Consolidated Technologies Inc. in Upper Marlboro.

She was active in the Montgomery County Chapter of the NAACP and with the Regional Council of the Metropolitan Washington Girl Scouts. She served as an area council member and troop leader of the Girl Scouts and as a Cub Scout den mother.

Besides her husband, survivors include a son, Dudley W. III, and two daughters, Linda J., and Marion A., all of Silver Spring; her mother, Agnes B. Smith Harris, and a brother, Donald L. Smith Sr., both of Washington, and another brother, William H. Smith Jr. of Los Angeles.

The family suggests that expressions of sympathy be in the form of contributions to the American Cancer Society.