The sidewalk surrounding Manhattan's Bryant Park is lined with posters promoting a new image of Lord & Taylor, the U.S.'s oldest department-store chain. In the pictures, members of some mythical extended suburban family smile as they frolic in their vintage Mercedes convertible or slide into a wooden canoe.

Despite their beauty, the photos and the inference that they epitomize American style seem jarringly anachronistic. At a time when fashion has become global thanks to the Internet and the access it provides to ideas, resources and products, American style is becoming increasingly difficult to define. At New York City's Fashion Week there were 259 designers of different nationalities--including Chinese, Thai, Brazilian, Japanese and Turkish--showing their spring 2008 collections.

"Fashion is no longer regional, and the notion of American sportswear is no longer valid, nor does it look current," says Robert Burke, a luxury consultant. "I've seen shows this week that could easily have taken place in Paris or Milan." More and more, it is the itinerant lifestyles of multinational designers--many of whom frequently travel around the world to visit factories, stores and suppliers--and the global reach of the Internet that inspire the clothes they send down the runway.

Take Tia Cibani, the Canadian-born designer of Ports 1961, a line that is produced in southern China and shown in New York. While Cibani commutes between New York City and Xiamen, inspiration can come from as far away as East Africa, as it did this season. Her collection, called Safiri, pays homage to African women's spontaneous sense of style and their imaginative fabric treatments such as tie-dyeing, rolling and wrapping.

Other popular destinations for spring included Rome, with Vera Wang excavating ideas from the city's ancient polycultural society and translating them into toga-like dresses, and Bali, where Diane von Furstenberg found bold floral prints. Japan--specifically its traditional folded-and-dyed fabric-printing technique, shibori--turned up on the runways of designers like Narciso Rodriguez, Proenza Schouler and Thakoon Panichgul.

"We grew up in a time of complete globalization," says Lazaro Hernandez, 28, who, along with Jack McCollough, designs the label Proenza Schouler, "so the boundaries are not as strict. We're young, and we don't have the money to travel that much, but we travel in our heads. We go online. With technology, you can go anywhere on the Internet." This season they found a trove of vintage kimonos in McCollough's parents' attic, and the trapezoidal sleeve shape became a major motif of their collection.

One of the reasons designers look so far afield for ideas is to stay one step ahead of the mass-market manufacturers that copy trendy fashions and sell them for much less. Designers like Hernandez and Panichgul say craftsmanship is what sets their clothing apart. "I don't think we could have survived in the late 1990s because minimalism, which was so popular then, is so easy to copy," says Hernandez. Indeed, consumers who want to buy a black sweater or a pair of black pants are inclined to go directly to H&M for the best price. As a result, Hernandez and McCollough feel the pressure to make their clothing even more ornate. This season, for example, they employed the French haute couture supplier Lemarie to embellish their clothing with rows and rows of tiny feathers.

"You have to develop a cult customer," says Panichgul, "someone who is looking for this kind of elaborate work every season." And someone who can afford it.