Doris Koo's business card says she's president and CEO of Enterprise Community Partners. But at heart, she's something quite different. She's a grassroots community organizer—maybe even the ideal social activist.

“She a remarkable woman,” says Jim Kelly, executive director of Providence Community Housing, a developer that builds affordable housing in New Orleans. “She’s a community organizer at heart and a developer by training.”

Like another well-known community organizer-turned-leader, Koo’s creed was established in Chicago. She got her feet wet in the Windy City in the mid-1970s—10 years before President Barack Obama came on the scene. She started teaching English as a Second Language (ESL) courses in Chicago’s garment district and soon became a pillar of the community. When immigrant workers needed someone to explain to local school officials that their kids needed time off for a doctor’s appointment, Koo was there to help them. Later on, after moving to New York, she watched as immigrants were illegally evicted from their apartments or forced to live in wretched conditions in Chinatown and decided to step in. It was Koo who organized a team of Brooklyn law students to take those landlords to court.

So, how does it happen that 25 years later, someone who was fighting the good fight on a fundamental level finds herself leading one of the biggest tax-credit syndicators in the country? Like many leaders of her generation, the slight, yet forceful, enthusiastic Koo has brought her ideas into the boardroom—and she is promising to step out of the shadow of Enterprise’s past leaders to create a new legacy for the firm. But with a financial crisis that’s hammering many of Enterprise’s biggest financial backers, she faces a climate that would make even the most steadfast community activist squeamish.

Columbia, Meet New York

If you didn’t know what Jim Rouse looked like before you drove into Columbia, Md., you’d know his face by the time you left. Walk toward the man-made lake by the Enterprise offices, and you’ll find a statute of Rouse. Inside the Enterprise offices, you’ll see pictures of Rouse and medals with his likeness. It’s easy to understand why—Rouse and his wife Patty helped build Columbia, and he launched Enterprise to assist local nonprofits interested in building affordable housing. Housing was Jim Rouse’s passion.