THIS year marks the 40th anniversary of Sloan Wilson's bestseller ''The Man in the Gray Flannel Suit,'' a novel whose title neatly described the corporate dress code of the 1950s. Yet if Wilson were writing today, he might need to rename his book ''The Man in the Cotton Twill Slacks.''
That's the conclusion a culture-watcher could draw after IBM announced last week that it was abandoning its longstanding formal dress code. Goodbye somber blue suits, crisp white shirts, and wingtips. Hello khakis, cardigans, and loafers.
The unstarched look, according to a company spokesman, will make for ''a more collegial work atmosphere.'' It will also test the theory that ''if you're comfortable, you can think better.''
Already, a quarter of American businesses allow a dress-down day on Fridays. Now, with IBM leading the way to all-week sartorial freedom, can other corporate giants be far behind?
Call it the end of an era, but don't consider it total progress.
A less rigid approach to business-wear offers advantages, of course. Assembling a serious wardrobe and caring for it takes time and costs money. Already financial analysts report that employees of the '90s would rather spend money on household goods than on clothes. Wide-ranging fashion choices also offer a welcome freedom from tyrannical designers, who can make entire wardrobes obsolete by dictating changes in hemlines and lapels.
But relaxed dress codes also raise questions: In an era of corporate downsizing, is ''downdressing'' a good idea? Supporters of casual business-wear could argue persuasively that when corporate axes fall, managers dismiss the best-dressed and worst-dressed with equal ease. Proponents of regular business attire could make an equally valid case that managers, given a choice between two workers, might subconsciously choose to keep the one who looks more ''professional.''
Then there are the inevitable gender issues. After two decades of hard-won progress, women now account for about 40 percent of middle managers. But given the disparities that still exist in the workplace, is there a danger that a casually dressed woman will be taken less seriously than a casually dressed man? Alas, the possibility exists.
Finally, if all events in life are created equal -- equally casual -- and no occasion is worth dressing for, will attitudes toward civility and manners become casual as well, to the point of indifference?
Ironically, just as corporate executives are loosening their ties, some public-school principals are tightening theirs by requiring students to wear uniforms. ''Looking good'' and ''looking sharp,'' a Seattle principal claims, ''creates a good atmosphere'' and improves attendance, performance, and camaraderie.
The old question, ''What should I wear?,'' will not necessarily be made easier by relaxing dress codes. A uniform corporate look, for all its seeming restrictions, can be freeing. A fashion free-for-all, on the other hand, can produce more anxiety than liberation.
Clothes don't make the man -- or woman. But they do make a powerful impression. This year marks the 20th anniversary of John Molloy's guide to business attire, ''Dress for Success.'' Although some chapter headings (''How to Get the Most Out of Investing in Suits,'' ''How to Maximize the Power of Shirts'') sound quaintly outdated in the wake of IBM's announcement, Molloy's advice still rings true: ''The way we dress has remarkable impact on the people we meet professionally or socially and greatly (sometimes crucially) affects how they treat us.''
Historian Anne Hollander reinforces that idea in her new book, ''Sex and Suits'' (Knopf), by stating, ''We live in a world of visible projections, and we are all visible projections in it. Like it or not, we all have looks, and we are responsible for them.''
It will be interesting, to say the least, to see how the newly freed spirits at IBM project corporate responsibility and authority while divesting themselves of their blue suits and white shirts.
A uniform corporate look, for all its seeming restrictions, can be freeing. Whereas a fashion free-for-all can produce more anxiety than liberation.