Though she confesses that her feet sometimes get itchy, Zelda Fichandler always is too involved to think seriously about projects that exclude Arena Stage.

A good thing too, for there would be no Arena Stage without the life force of its co-sounder and producing director.

This is the time of year when Fichandler is into plans for next April and has dreamy notions about 1978-79. Her more immediate targets are Oct. 7, when "Nightclub Cantata" opens in the Kreeger and Oct. 14, when "The National Health" bows in the Arena.

Fichandler looks almost indecently like the slim, brunette 24-year-old who begin talking about a professional theater for Washington in 1949. The brown eyes, quite unwrinkled, still gleam when she speaks. The major difference is the calmer, more measured conviction achieved only through experience.

Apart from Arena's altered status from August, 1950, when "She Stoops to Conquer" was its introductory play, what else has changed?

"There now are links betweem regional theaters," she replies. "It's a natural, far easier, cooperative development and while it's old in theatrical history, it's new for American theater production.

"Last season, for instance, there were three regional productions of Christopher Durang's 'A History of the American Film.' Introduced at Connecticut's O'neill Center the summer of 76, it got three production bids, from the Hartford Stage Company, the Los Angeles Mark Taper and ourselves. There was no attitude of any group wanting to be 'first.' That didn't matter. We all did it. Of course I'm delighted that the New York producers are choosing David Chambers, who staged it for us; that's not the point.What matters is that a very fine satire was introduced without the traditional New York hit-or-miss expectations. The regional theaters believed in it and brought it to life.

"This season, in March, we'll present Studs Terkel's 'Working,' which we're sharing with Chicago's Goodman Theater, which will do it first.

"Funny things about Studs' great book. I'd read it three years ago, just before meeting him. As soon as I saw him I begged him for dramatic rights. He had just assigned them to Stephen Schwartz, the 'Godspell'-'Pippin' composer. I'd been thinking of it in film or TV terms, certainly not as a musical and I concluded well, that's that.

"Then, last spring, Studs and Stephen thought of me. It had to be done first in Chicago because that is where Terkel is based for his radio series. It's such an original treatment, and Stephen's music and lyrics are marvelously resourceful. He also will direct, for this is his concept. I believe this collaboration with Goodman will be one of our year's highlighs.

"Nor am I saying we're the only ones this kind of production sharing. "The Shadow Box" was introduced at the Mark Taper, then at Long Wharf, New Haven, and went on to New York for the Pulitzer and the Tony.

"The Los Angeles Center Theater Group has just announced a collaboration with the Brooklyn Academy of Music Theater Company, planning two joint productions a year. First will be Shaw's 'The Devil's Disciple,' to open in Los Angeles and then go to Brooklyn, which will be sending Los Angeles 'The New York Idea,' the Langdon Mitchell play it revived last spring.

"We took up Jon Jory's Louisville Actors Theater 'Tricks' and through the Theater Communications Group, we members keep in touch with emerging talents. We share annual auditions.

"Such collaboration is the big difference from how it was when we began. More important than the economic side is the artistic development cooperation makes possible.

"While it seems news for American theater, Boston, Chicago and San Francisco once created their own theater. And in the European tradition the municipal and state theaters often produce new plays simultaneously and inter-pretations.

"Choosing the season's plays is a winnowing experience. I whittle down to about 16 plays I really long to do, knowing only half can happen. I had such strong hopes to start with a visit from the Negro Ensemble Company, but that has not worked out. Money, lack of it, is an alarming threat to Douglas Turner Ward's admirable New York ensemble.

"This winter we will revive 'A Streetcar Named Desire,' which was on my first list for last season. No, the casting is not set. That always depends on performers' availability. I can understand actors holding out for alternative roles elsewhere.

"This season, for instance, Howard Witt, with us for so long, has decided to take his chances in Los Angeles. Diane Wiest already has done two roles for Joe Papp in New York. I wanted Roy Brocksmith, who was so arresting in 'The Lower Depths,' for parts this fall, but he has two jobs in New York, where he lives with his family.

"We'll be doing our first 'Hamlet' oin March. This will be staged by Liviu Ciulei, the Romanian director who gave us such a brilliant 'Lower Depths' last season. He has a concept fot it in the Arena which we've discussed fully.

"I had tried for the first American production of Trevor Griffiths' 'Comedians,' but though it failed at least at the box office, in New York last season, I believe it's worth its second chance here in January. Griffiths will make some changes in it himself.

"I don't think I ever have seen quite so original a talent as Elizabeth Swados,' who will be adding new material to the Kreeger's opening 'Nightclub Cantata.' Her mixture of wit and seriousness is remarkanle ane we'll have New York's Top of the Gate's cast of last winter. Since then she has contributed the music for Andre Serban's productions of "The Cherry Orchard" and 'Agamemnon.'

"We'll be using the Old Vat Room more. 'Starting Here, Starting Now,' the Richard Maltby Jr. and David Shire revue I flipped for last spring at the Manhattan Theater Club, will be the first of three nonsubscription productions there, where we also will continue the new playwrights' series, In the Process.

"As for time to think, so vital for me, I now have two playreaders I trust, so I don't have to feel guilty about piles of scripts demanding to be read. Now I have only 10 or a dozen at my elbow, winnowed from the hundreds I had to do myself.

"How do I read plays? Above all, I never start one unless I know I have the tieme to finish. It's more possible at home than at the office, where the phone always is a threat. I sit in a comfortable chair and plow ahead. Sometimes I'll read one several times over. You simply cannot be interrupted.

"The future? I can't let myself think about it too much. Where is the money to come from? Federal subsidy seems the only answer. Ours - and all regional theater - is a nonprofit, deficit operation. There is no real corporate support in Washington for the arts. Ours is not an industrial community.

"That's why our individual donors are so vital to us. Tax deductible gifts can mean matching grants for us and special privileges for donors, but in this past year foundations have reduced their support sharply as their own resources have dried up.

"I am not confident about our survival. Washington has lost performing groups before and theaters have been snuffed out in major cities. Tom (Thomas C. Fichandler, her husband and Arena's managing director) performs miracles and makes it possible for me to concentrate on our creativity. But often it seems to me that our survival, let alone our growth, is a very chancy thing.

"So while some of me now is living in 1978 and '79, another part of me is not certain there will be a 1979. As for the '80s, I just block 'em out."