"The play's the thing," William Shakespeare noted 400 years ago. But for one nonprofit arts group in Chicago, it's no longer the only thing. Redmoon Theater, known for its surreal plays, is venturing into the $500 billion event planning industry, taking its place alongside entrepreneurs operating their for-profit businesses.

Conventions in the Windy City can hire Redmoon's actors to give their events an edgy, artsy vibe--think women in white-powdered wigs serving appetizers off their table-size hoop skirts ($2,300) or a 1920s diva on a wheeled chaise lounge tossing roses to her guests ($3,600).

The productions earn great reviews and contribute a significant percentage to Redmoon's annual budget. But in a market crowded with small businesses competing for the same audience, how can entrepreneurs compete with nonprofits for center stage?

It's a question that faces entrepreneurs in almost every field. According to a 2008 study by the Urban Institute, sales of goods and services account for about 70 percent of revenue at public charities, far ahead of both government grants and private donations. And thanks to the internet, that figure is likely to climb higher still: eBay now counts more than 13,000 nonprofits registered with its Giving Works program, which allows people to buy and sell for a cause.

Kathleen Carlson, 51, principal and co-founder of Chicago-based event planning company Carlson Frank LLC, says the secret to staying competitive is creativity and flexibility. The company stages up to 20 events a year with budgets ranging from $30,000 to $1.5 million. And though Carlson is a fan of Redmoon, she notes that the theater's edgy image locks it into a certain type of event.

"We can be much more flexible in terms of seeking out a venue that works for a client," she says. For a recent client looking to shed its "cowboy" image in its industry, Carlson arranged a yachting-themed weekend in Newport, Rhode Island--an event light-years removed from white-wigged women in hoop skirts.

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