Condé Nast Traveler editor in chief Pilar Guzmán on dressing up for the journey.

I’m always amazed when I see the hordes of Spring Breakers pouring out of planes wearing cutoffs and flip-flops, as if the flight were just a four-hour prelude to a day of swim-up-bar daiquiris and tanning. As much as I travel, I still feel an anachronistic sense of duty to dress for the plane. Which isn’t to say I wear pencil skirts and pantyhose. Come to think of it, I don’t even own a proper suit anymore. The definition of appropriate dress has evolved a lot since the dawn of commercial air travel, and these days the international uniform of a pair of fashion sneakers with a men’s-style trouser or nice jeans and a button-down shirt is a safe bet for both men and women. Clean and casual—but not too casual.

Whether your fashion sensibility skews traditional, street, or ladylike (I do envy the dame of another era, boarding a flight in a shift dress, carrying only a small structured handbag and a book), certain sartorial truisms transcend taste. Like, don’t pad onto the plane in pajama bottoms and slippers with a pillow, as though you just rolled out of your mother’s station wagon after a sleepover. (Unless, of course, it’s a silky pajama-style pant meant to be worn outside the house.) Short shorts on the plane, even to and from the Caribbean, are still a head scratcher. Beyond the impropriety of it, planes tend to be airborne tundras with a shortage of blankets; they’re also filthy, and scant clothing and open-toe footwear put skin in contact with too many unsavory surfaces. Not to sound like Andy Rooney, but don’t get me started on socks in the bathroom.

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