Neil Simon has business in Los Angeles, Chicago and New York this week. He has no business in Washington, and that's what brought him here Wednesday afternoon, just in time to watch the sun set over Roslyn from the ninth floor of the Watergate Hotel.

"In the past -- before the Kennedy Center -- Washington was always a must for me," said Simon, settling into an extremely blue armchair in a suite almost large enough to accommodate one of his hotel-based plays.

"The Odd Couple," "The Prisoner of Second Avenue" "The Sunshine Boys" and Promises, promises" all played the National Theatre on their way to Broadway, he recalled. But he has never had a play produced at the Kennedy Center.

"It doesn't mean anything in terms of money or in terms of my career," Simon said. "There are always places for us to play. I'd just like to be able to play the Kennedy Center. It's the theater that represents the theater in this country."

He has never met Roger L. Stevens, chairman of the Kennedy Center. "Generally, I don't get very involved in these things," he says. "Manny Azenberg is probably the best manager of plays in the business." Azenberg, who has produced every Simon play since "The Sunshine Boys," has told his prize author -- and anyone else willing to listen -- that Stevens has kept Simon's plays out of the Kennedy Center.

Last year, Azenberg brought a touring company of "Chapter Two" to the Warner Theatre, which he had helped re-outfit for legitimate plays, as a way around what he saw as the "monopolistic" control of the National Theatre by the Kennedy Center, which until recently acted as the booking agent for the National. Simon did not come here with the production.

"I have not been here in a long time," he said. "Next time, I hope to come with a play."

Simon was here to speak at yesterday's closed meeting in the offices of Sen. Daniel P. Moynihan (D-N.Y.), where a group of New York theater figures had gathered to discuss the center's programming policies.

Simon has only two shows on Broadway right now -- a relative decline in exposure for America's one-man comedy factory. But that's not all he has working.

He and Azenberg had flown into Washington from Chicago, where the first national company of Simon's "They're Playing Our Song" is in previews. Washington is not on the company's agenda. "everything leads back to why we're here," said Simon.

He and his wife Marsha Mason, live in Los Angeles, where his latest play, "I Ought to Be in Pictures" (with Tony Curtis) is now in rehearsals, and where a Simon-written movie, "Seems Like Old Times" (with Chevy Chase and Goldie Hawn) goes into production in the spring. This weekend, Simon will be in New York, where the stage version of "Chapter Two" will close after two years at the Eugene O'Neill Theatre, which he happens to own. Not entirely by coincidence, the movie of "Chapter Two" (starring James Caan and Marsha Mason) has its first public screening a few hours after the final performance of the play.

It is a crowded schedule, "but I have enough time for my private life too," he said. "I balance it out pretty good. I have an office that's situated across the street from the Beverly Hills Tennis Club, and I manage to play three or four times a week. I work about three or four hours a day, never more than that . . . I could never work on weekends -- too many good football games."

Until "The Sunshine Boys," Simon was dissatisfied with almost all the movies he had worked on. Moving from New York to Los Angeles made it possible to keep a closer watch over the movies (the movie also provided material for "California Suite"). And he has kept the plays under close surveillance too, simply by trying them out in Los Angeles.

Another professional-personal problem surfaced about two years ago, when Simon developed neck trouble and diagnosed it as the result of too many hours cramped over a typewriter. He saved his neck by resorting, at regular intervals, to pen and paper.

He expects to solve the Washington problem, too -- and already has an idea that the solution will have a lot to do with "better communications."