As it has become customary this time of year, area residents are running the streets for the sake of fitness, community unity and the business of helping others.

RunDunwoody 2012, set for Sunday, is the latest such offering.

“It’s evolved so much from a concept of us just wanting to reach out and create an event supported by a host of different elements in the community,” said RunDunwoody co-chair Kelly Hundley. “Now, in year three, we feel like we’ve established a fair amount of traction … groups are contacting us to volunteer.”

Organizers hope to attract an event-record crowd of 700-plus to this year’s event, presented by the Rotary Club of Dunwoody.

While a one-mile family fun run and tot trot round out the day, the 5K run essentially serves as the main event.

The 5K, a Peachtree Road Race qualifier, features a “fast” course — from Perimeter Place across the Perimeter flyover bridge and more — that also happens to be scenic, with views of hillsides and ample trees in between, said RunDunwoody co-chair Kathy Brandt.

RunDunwoody has plenty of company these days.

“Since we started planning for this event three years ago it seems like we have some sort of 5K or another in the Dunwoody area when the weather’s nice … and they’re all for great causes,” said Hundley.

RunDunwoody is no different, Brandt added.

“All of our proceeds benefit the community … from the start, first responders — [local] police and firefighters — have been recipients of some of those funds … service is our focus.”

Elsewhere, DeKalb County’s inaugural Exchange Community Breast Cancer Walk/Fall Festival is set for Oct. 27.

The event, to be held at the Exchange Intergenerational Recreation Center, features a 5K walk scheduled to start at 9 a.m., followed an array of festivities — ranging from games to a car and bike show. “Everybody’s excited about it … pretty much everybody knows someone affected by breast cancer,” said Exchange Center director Nicholas Clark. “We have to take care of our own community and we have to invest in our own community.”

Proceeds from the event will be split between the Susan G. Komen for the Cure and an Exchange Center fund used to purchase fitness equipment.

The center, nestled on a 33,000-square foot campus in Decatur, welcomes several hundred patrons of varying ages daily. Designated spaces at the facility include a walking track, dance studio, wi-fi café, art room, gymnasium and computer lab.