NEW YORK -- Imagine trying on clothing at a department store and getting immediate feedback from pals that pops up on the mirror of your dressing room.

IconNicholson, a New York-based full-service interactive agency, is hoping to make such a virtual experience for young shoppers commonplace over the next three to five years at department stores across the country and expects to launch its first test with trendy fashion designer Nanette Lepore over the next three to six months.

The concept, which was displayed at this week's National Retail Federation's annual convention, combines young consumers' passion for online socializing with their love of shopping and could help drive teens back to department stores.

The technology works like this: consumers try on clothes in front of a three-panel interactive mirror, which also serves as a kind of computer screen. Shoppers tap on the screen and send messages to friends or to members of their social networking site like facebook.com, alerting them to a private, protected URL site. Their friends then can virtually enter the dressing room, sending back comments about the designs as feedback that pops up on the mirror.

Joseph Olewitz, senior vice president of client relations at IconNicholson, which is using the exhibit at the NRF show to test reaction from store executives, said the project is aimed -- but not limited to -- the 17- to 24-year-old.

These young shoppers, he said, are "social," he said. "They are IMing and phone messaging each other all the time. They shop in groups. This will appeal to them."

IconNicholson and Lepore still have to work out such issues as whether the experience should be limited to the shoppers' list of friends or be open to the public. Mr. Olewitz said the company is close to signing a deal with a department store, but he declined to be more specific.

Ms. Lepore couldn't be immediately reached for comment.