Comedian and actor Robin Williams once said, "Spring is nature's way of saying, 'Let's party!' "

And there's no shortage of stylish duds to wear to the celebration, given the new designs already finding their way into stores.

Seasonal demarcations are blurring, with clothes each season a seeming repetition of the prior. Although one might wish more designers were creative mavericks, the upside is a delightful profusion of attractive options for women and men for spring through summer.

Dignified elegance with a whimsical flair pervades all aspects of dressing for women this spring and summer, while comfortable layers and a handsomely tailored combination of preppy athleticism and polish are general themes for men.

Variety has always characterized womenswear, but this season's exuberant offerings derive from inspirations that are all over the map -- literally -- from famous paintings and iconic photographs to Indian and African influences to trends from the '40s through the '80s.

Bold florals didn't take a winter break, and they bloom in full glory now. Ikats, ombres and color-blocks also pick up steam for spring, black-and-white combinations are fresh and inventive, and saturated shades of chartreuse, turquoise, fuchsia and lemon make looks pop in tasteful moderation.

Not-quite-white neutrals such as bone, blush, chalk and champagne emerge from winter as alternatives to the requisite snow white, and warm-weather perennials such as polka dots, plaids and stripes are upstaged by brushstroke prints and abstract graphics.

Designs are cut to complement the human form, whether draped architecturally, fitted with no-margin-for-error precision or both at once.

This trend is most noticeable in the dress, the queen of go-to pieces this season in more colors, prints and silhouettes than one can count. Dresses have dominated women's fashion for more than a year, and the effortlessly feminine garment works for all shapes and sizes.

"It's a no-thinker," said Nancy Stillson, owner of Occasions in Squirrel Hill. The recently opened women's boutique at 5873 Forbes Ave. specializes in dresses for work, relaxation, cocktail parties and formals, featuring everyday and red-carpet designs by labels such as Teri Jon, Dina Bar-el, Badgley Mischka and Marc Bouwer.

"Buying a dress is like one-piece shopping," said Ms. Stillson. "Women like it because it's easier. You don't have to match a bunch of components like with a skirt or pants. And there's nothing that catches a man's eye like a red dress."

Gowns this spring are dominated by one-shoulder, asymmetrical, halter and goddess styles. Pleats, ruffles, intricate beading and stonework add rich texture to soft fabrics, and in-your-face colors such as royal blue, coral, lime and hot pink allow the wearer to stand out in a crowd.

Skirt silhouettes are across the board: A-line roomy, pencil-sleek, bubble hems and to-the-floor lengths with embroidered and dyed hand-detailing.

The high waist remains a key look for pants, with legs cut cigarette-skinny or elephant-wide. Gauchos and jumpsuits offer casual and sporty alternatives, and the latest walking shorts are matched with knit tops, breezy blouses or matching jackets.

Accessories continue to make dramatic statements. Jewelry is intricately designed and scaled big to command attention, bags range from colorful clutches to gigantic hobos, and footwear trends encompass such wide-ranging styles as flats, platforms, metallic gladiator sandals, multicolored slingbacks and patent-leather peep-toe pumps.

The glamorous shift in women's fashion in recent years seems to have had an impact on menswear design. Men's looks have gotten dressier and more polished, but the shift has been much more subtle.

The influence of European designers, combined with a yen for the '60s, has resulted in more tailored, body-conscious silhouettes, especially pants and suits.

At the same time, an intriguing mix of the skateboard culture, urban streetwear artistry and Southern California cool have made sportswear even more tactile and vibrant. There is more color and more neo-abstract imagery, as witnessed by the tenacity of the graphic T-shirt.

But the resulting looks are calculated and pulled-together, not random and reckless as it was in the '80s and '90s. There is structure to layering but not so restricted that individual personality cannot shine through.

Consider the three must-haves for men this spring, according to Charles Spiegel, owner of his self-named men's shop and the Garage store-in-store in Squirrel Hill: "A great pair of fun shorts, a cool blazer not worn with a shirt and tie but with khakis or jeans, and a novelty shirt."

It's no coincidence that the items can be worn separately or together and in myriad combinations. American men still crave casual -- which they equate with comfort -- but are less hesitant than in the past to combine elements of sporty and dressy to create a hybrid look that works for them.

For example, Dolce & Gabbana's silk-wool blazer over a V-neck sweater and jeans symbolizes what has become a contemporary go-to look for even the most fashion-challenged guys. And few men will not find appealing the monochromatic black look of a cropped tech-fabric jacket over a black shirt, tie and trousers by Ralph Lauren Black Label.

Fellows under 45 are buying more suits, but many eschew the more conservative looks donned by older men. The younger set is more apt to assemble a sleeker look that features slim flat-front pants, a three-button jacket, a colorful polo or open-collar shirt in a funky print, and sneakers or other casual shoes.

"I think the world is reacting to novelty," said Mr. Spiegel, citing snapfront shirts by Thierry Mugler and increasingly popular styles by Etro and Robert Graham characterized by imaginative prints and colors in edgy combinations.

"People are reacting to freshness. Slimmer silhouettes. Color. It's not all black and gray."

Innovations and color, in fact, have sparked new interest in denim, observed Mr. Spiegel.

"The reintroduction of destroyed denim has people buying jeans again," he said. "Dark, slim, unwashed denim took a lot of people out of the market."

Interesting trends in men's accessories include cuff links, statement watches, novel belt buckles, big carry-alls and casual brimmed straw hats.

"The fashion sneaker is the 'it' thing this spring," said Alison Sokolove, a fashion editor and trend analyst with the Tobe Report. "Pattern or lizard or colorblocking or artist collaborations."