In November, apparel maker Life Is Good moved about 60 employees, who had been spread over three Boston-area offices, into one new, open-plan space. The change brought together members of the company's product and marketing teams with its nonprofit foundation. But the arrangement didn't spark as many spontaneous creative collaborations as the management team had hoped.

So HR director Stephanie Manners asked for volunteers to take part in a workshop led by teachers from Boston-based theater group Improv Asylum. In the two-hour session, one exercise that stood out for the 20 participants was the simple "Yes, and…" game. Two people at a time volunteered, with the first starting a conversation with a statement ("I really love my dog").

When the second responded with a "but" statement ("But dogs really smell"), the dialogue ground to a halt. On the next go-around, the partners were directed to begin each response with "Yes, and…." Now they were talking.

It was a powerful demonstration of how to build on someone else's ideas, rather than shutting them down to advance your own. "You really see how the word no is such a showstopper in conversation," says Manners.

Many other companies are turning to improv to foster communication and creativity. A workplace culture of "Yes, and" tends to be one where innovators feel comfortable, says Daena Giardella, who teaches an improvisational leadership class at MIT's Sloan School of Management. "Innovation thrives in an atmosphere of safety and non-criticism," she says. "Improvisation builds a muscle for trusting our own impulses and ideas, before we have to analyze how good they are, as well as helping develop an open-mindedness toward other people's ideas."

There's a common misunderstanding that improv is all about being funny. It's not. "You don't have to feel pressure to invent jokes and come up with puns," says Chelsea Clarke, a performer and instructor with improv group Upright Citizens Brigade in New York City. "The product is often funny, but it's mostly about listening and supporting each other, committing to a reality you're making up on the fly."

In a typical session, there's not much time to get stage fright--expect to jump right into warm-up exercises designed to get the group mind working. These can include simple word games, communicating in gibberish, or playing "catch" with imaginary balls. Such exchanges can help participants tune into nonverbal signals. "It's not just about listening to words, but subtext and intent," says Clarke. "That's valuable in business, where a client or partner might be telling you one thing but communicating something else through body language."

Clarke might have a group pretend to be a certain kind of company, like an ad agency, and give them a crazy product to give a presentation about off-the-cuff. The key to a successful pitch is not undermining your colleagues. "You have to listen to each person's choice that came before," she says. "You might have a great idea, but if it doesn't fit with what the last person said, you have to check it. That's a hard thing to do--but improv helps you realize that you're going to have more good ideas."

At Life Is Good's new office, improv training has had a lasting impact, says Manners. "I notice that in meetings now, there's a lot of language like 'Yes, we could do that--and we could also consider this.'"