ONE BLUSTERY, GRIDLOCKED SEATTLE evening, a small, white-haired, red-nosed woman opens her door to me. A cold is responsible for the brightness of Kate Wilhelm's nose, and also for the thickness of her voice as she mocks the staggering size of her hotel suite: "It's got a laundry room, for crying out loud. Did you bring your laundry?" My large shoulder bag contains books, not dirty clothes: Wilhelm's latest hardcover, Defense for the Devil, sold as a "courtroom drama," plus The Good Children, a new Wilhelm paperback I unboxed at the bookstore just last night. I'm only halfway through Defense for the Devil's eerie hybrid of Shirley Jackson's gothic horror and E. Nesbit's juvenile adventures, but I've already decided it's my new Wilhelm favorite. I've also brought a reprint of Wilhelm's Hugo Award-winning classic on clones, Where Late the Sweet Birds Sang. I spread my purchases on the coffee table, and sheepishly add two yellowing, older Wilhelm books: Juniper Time, a maddening thriller about space stations and self-deceit, and Margaret and I--my first favorite--an erotic tale of Jungian psychology. It's a small but fairly representative sampling of Wilhelm's 41 books.

Throughout her wide-ranging oeuvre, Wilhelm's writing spurns superficial descriptions while vividly conveying ineffable essentials. Defense for the Devil completely lacks noirish, metaphor-laden scene-setting passages; protagonist Barbara Holloway never pauses to appraise herself in a mirror or handy shop window. This heroine focuses on action, motives, connections, histories--subsurface tensions rule her life, as they do the lives of all Wilhelm's characters, whether they're dealing with world-wide ecological disasters or tightly framed domestic tragedies.

That's just the way Wilhelm's mind works. Her husband, she says, can tell you the exact color of an old friend's eyes. "What I recall is the way he walked, how he held his coffee. I'd never be a good romance writer." Too many irrelevant details to keep track of: color of eye-shadow, sleeve-length, hairstyle....

Wilhelm shrugs off these annoyances with the same determined air she shows when dealing with questions of genre. It's a subject I can't help but bring up, though her publicist has warned me against it. I feel like I'm discussing astrology with Carl Sagan. Wilhelm listens patiently and responds carefully, as if only the most thorough answers will satisfy my unhealthy interest.

Fiction is fiction. The public library where she read as a child didn't categorize by genre, and she sees no reason why anyone else ought to do so. Readers who pay attention to that sort of pigeonholing miss a lot of good writing.

On a personal level, she says, "I hate being called a genre writer, and I never think of myself as one. I would be terrifically bored if I had to do one kind of book over and over. I would stop writing; it's that simple."

I bring up Walter Mosley as an example of someone else who's written in more than one genre. Mosley's Easy Rawlins drives around L.A., asks tough questions, gets shot at. But in his new stand-alone, Blue Light, a mysterious ray from outer space animates corpses and makes the hero a telepath. Two different realms of action, two different categories. The classifications must be less confining if you switch around among them, right?

"I just don't think in those terms," Wilhelm explains gently. If science fictional elements appear in some of her novels, it's because sci-fi is a part of the world we live in, a part that happens to apply to these particular works.

But if Wilhelm's writing doesn't arise from any category, it settles down in one when finished. Some publishers print genre labels right there on a book's cover. Others are more subtle, using quotes or comparisons to forge links to Grisham or Jordan or other best-sellers. Bookstores shelve by category first, then by author. Readers often refuse to follow genre-jumpers from section to section, and critics misunderstand their intentions.

Margaret and I, a case in point, "got a terrible review from someone who said it was bad science fiction." Wilhelm loses her patina of patience. "I never said it was sci-fi at all, nor did the editor, the book jacket, the catalog, the publicity, or anything else."

Well, the book does feature a ghostly physicist and his secret notes on experiments with time travel. But there's also an arrogant politician, and a morally ambivalent but sexually skillful grad student. The protagonist is Margaret's nameless unconscious, and the action centers on her self-integration. It's beautifully written, with several highly arousing passages. So why judge it by genre standards? Why categorize it out of anyone's reach?

Margaret and I was first printed in 1971. Since then, says Wilhelm, "sci-fi has merged so much into the mainstream in so many ways, that it probably doesn't occur to anyone to ask exactly what Kurt Vonnegut writes, or what he used to write. He's simply accepted as a fine writer."

Kate Wilhelm is another one. Though she's had to try different publishers from time to time while jumping genres, she has always managed to land gracefully on her feet.