Marriott’s innovation lab at its Bethesda headquarters has model guest rooms with moveable walls and furniture. (Courtesy of Marriott International)

Marriott International wants to reinvent itself — and it’s looking to Generation Y for help.

The 86-year-old hotel company recently began asking 20-somethings for ideas re-imagining the hotel of the future, with a chance to actually have a hand in making it a reality.

In the two weeks since the company introduced a new Web site asking customers what they’d like to see in guest rooms, more than 100 ideas have streamed in: Neck pillows with built-in music, an app for selecting toiletries, free beer during check-in. An initiative called ‘Don’t worry, your first bag is on us,’ would cover the cost of customers’ luggage fees, while a room-service app would allow guests to order food using their smartphones.

“We are definitely in transformation mode right now,” said Mara Hannula, vice president of global marketing at Marriott Hotels. “This is about having conversations with this new generation instead of just pushing things out and hoping that they work.”

Users are encouraged to submit multiple ideas and vote on their favorites. Five finalists will be picked every month between now and September. One winner will be flown to New York City to develop his or her winning idea.

“We have never done this comprehensive of a campaign,” Hannula said, “but we really want to change how our brand is positioned and perceived.”

By 2018, Marriott says more than half of its business travelers will be millennials — the generation that roughly spans current 21- to 34-year-olds. And, hotel executives say, their needs are different from the generations that came before them.

“They’re mobile and global, they demand style and design, and they seamlessly blend work and play,” Hannula said. “And technology is really important.”

Across the industry, hotels have begun looking for new ways to attract younger guests. WiFi and iPod docking stations have become more readily available, and hotel lobbies have been redesigned to include more communal spaces for hanging out.

At McLean-based Hilton, that push has included new Web-based advertising campaigns designed to reach younger travelers. The company’s line of Hampton Hotels picked seven millennials with online followings to travel the country, stay at its hotels and tell their peers about the experience. The travelers’ tweets, Facebook posts, Instagram photos and Vine videos were compiled into a 30-second commercial the company is promoting online.

“Millennials are the first generation that don’t know a world without the Internet, iPads and smartphones,” said Anna Harris, director of brand marketing for the company. “We had to show them that Hampton has everything they’re looking for — and we had to do it in a way that would be more effective than shooting a TV spot or running a print ad.”

A sprawling new innovation lab in the basement of Marriott’s Bethesda headquarters has offered a new playground for the company to test out ideas.

Among the 10,000-square-foot facility’s offerings: Model guest rooms with walls, closets and furniture that can be moved around. Designers, architects and focus groups are routinely invited to configure the rooms to their liking and offer feedback.

“We’re using that space as a way to say, ‘Look, we don’t have all the answers. We need insight,’” Hannula said. “The good news is that the customer really loves to be part of that process.”

The company plans to introduce updated guest room designs early next year. There are other projects in the works, too. Marriott is rolling out a mobile check-in app and is in the process of redesigning its showers — but not without asking younger customers for feedback.

We’ve learned that people love to talk about their ideas — especially generation Y,” said Katie Krum, director of eCommerce for Marriott Hotels. “Now we’re looking outside the walls of [Marriott] to uncover new ideas.”