About 25 people milled around Goudy Elementary School in Uptown on a recent Tuesday evening.
A man in a business suit stood next to another wearing a turban and sweats. There were blacks, whites, Asians. Men, women, children.
The diverse group had gathered for the same reason: to improve their health -- and the health of their North Side neighborhood.
"All that walking was good exercise," said Cook, who used to tip the scales at more than 300 pounds. Then he had gastric bypass surgery and "something clicked."
"I wanted to help other people take control not only of their health, but of the streets," Cook said.
At 6:30 p.m. on Tuesdays, Cook and his crew of community members convene at Goudy to hear a short talk on nutrition, fitness, street smarts -- the topics vary each week. Armed with clipboards, they then set off on a fitness walk around the neighborhood, jotting down the location of graffiti, overgrown trees blocking streetlights and other issues that need the city's attention.
The idea isn't just for them to spot problems, but for problems to spot them.
"It's kind of like taking back the streets," said Allen Turner, 38, a father of two who's lived in his Uptown townhouse for 13 years. "If we're out here, the thugs won't be."
He said as recently as last year, gangs, drugs and fights were getting out of control near his home on Winona.
"It got pretty crazy," said Turner, a video game designer. "We had a meeting with police, the alderman, the assistant principal at the school ... they heeded my call, so I felt the least I could do was do my part, too."
Turner and his family routinely turn out for the Tuesday night walks, which started informally last summer but became a full-fledged CAPS program this year.
CAPS Director Beth Ford said similar programs are springing up in other districts.
"The idea is really starting to catch on," she said. "There are a lot of neighborhoods where this kind of a walking program makes a lot of sense."
Local businesses pitch in to help make Uptown's Healthy People, Healthy Blocks work.
Galter LifeCenter, a medical fitness facility affiliated with Swedish Covenant Hospital, sends experts to the meetings to talk about diet and exercise. The fitness center outfitted everyone with pedometers at a recent Tuesday meeting so people could work toward a goal of 10,000 steps a day.
Jewel and Dominick's take turns donating fruit each week, and Flourish Bakery Cafe kicked in a gift certificate for a raffle.
Elizabeth Derrico, who lives on the border of Uptown and Edgewater, attended her first Tuesday night walk earlier this month.
"This is a great community-building activity -- and I get my exercise in," Derrico said.
"Let's face it: this is a neighborhood not without its problems," she said. "It's important to have a community presence out here."
Addis Clinton agrees. This single dad happened to be walking his young daughter in her stroller when he came across the group. He asked what they were up to.
"We need you all down there by Wilson," Clinton said.
"I'm a product of the streets myself," he added. "I wish we had something like this when I was growing up."