Scott L. Kirkpatrick, 74, who retired a dozen years ago after 20 years as manager of the National Theater, died July 25 at Georgetown University Hospital. He had leukemia.

Mr. Kirkpatrick's association with the National Theater started years before 1954, the year he became its manager. Born in Forrest City, Ark., he came to Washington in 1933 to study law at George Washington University and quickly discovered the theater's second balcony, where seats were then 55 cents.

Although he completed his law studies, he jumped at the chance to take a public relations job at the National in 1942. He stayed until Aug. 1, 1948, when the theater gave up stage productions as a result of joint action by playwrights and players in protest against racial segregation policies.

Having achieved a name in the information field, Mr. Kirkpatrick joined the National Symphony and later the Ballet Theater. When the National resumed stage plays, manager Edmund Plohn offered him the post of assistant manager. When Mr. Plohn retired in 1954, Mr. Kirkpatrick got the top job.

To Scott Kirkpatrick, the National Theater was Washington, the political as well as the residential city. With a congressman as a brother-in-law (the late Rep. E.C. Gathings, an Arkansas Democrat), he introduced political benefits, then a novelty, for National productions. Though the Woman's National Democratic Club was the first to take up his idea in 1957, Republican benefits soon followed.

The result was that Mr. Kirkpatrick was widely known not only in residential circles, where subscriptions mounted to 18,000 members, but also on Capitol Hill. In 1964, he ran for alternate member of the Democratic National Committee in the D.C. party primary.

But politics always took second place to the National. Mr. Kirkpatrick gloried in taking people around the old theater, which, he carefully explained, was "the fifth theater building on its site since 1835." His tours formalized into post-performance events for school groups, which he always encouraged with cut rates because "the young are the future of the American theater." His efforts to capture youthful audiences included requests to his visiting stars to meet with school groups for autographs.

Since his retirement in 1974, Mr. Kirkpatrick taught several courses in theater management at the University of the District of Columbia. Like many other "retired" persons, he claimed to be writing a book on his varied theater experiences. "But," he would tell his friend Robert Pitts, a longtime Frederick schoolmaster, "I'll get to it tomorrow."

Mr. Kirkpatrick, who never married, is survived by a brother, Otto Kirkpatrick of Forrest City, and two sisters, Virginia Dale Pilkington of Quitman, Ark., and Folise Gathings of Burke.