Diagnosed with Asperger’s syndrome, narcolepsy and other neurological problems, Kevin Denslinger had plenty of challenges as a teenager.

When he graduated from high school and moved into his own house and got a job, it seemed he had climbed the mountain. But on top of that peak was a solitary world.

“I usually just stayed inside,” said Denslinger, 35, a bearded gentle giant. “I didn’t know how lonely I was until I came here.”

The “here” Denslinger was referring to is the day program at “Just” People, housed in a commercial building in a Norcross industrial park, where more than 100 adults with Asperger’s, head injuries, Down syndrome and other developmental disabilities come to find a booming social life.

As he spoke, Denslinger was surrounded by young adults singing Christmas carols, playing games and chatting. The smell of hot oil and spices wafted into the air from the nearby kitchen, where a group of Denslinger’s peers was learning how to make chicken stir-fry. Others drew pictures or watched a Will Smith sitcom.

The scene was a far cry from the world Becky Dowling encountered 17 years ago, when she began putting together the plan for the nonprofit that would be called “Just” People.

Back then, the mentally disabled were regularly “mainstreamed,” rather than brought together in communities of their peers. The idea was to integrate the disabled into the world at large. But, said Dowling, no one was lining up to make friends with these functioning adults. No one was taking them out to sports events, or movies, or inviting them in to card games or on shopping trips.

Under the name “Just” People, she started organizing outings for groups of the disabled. The group grew, and she helped several get apartments. Eventually her buses were spending hours just picking up clients. Dowling wanted to centralize the group, and, in 2004, she found a parcel in Roswell where, with the help of developer Larry Doyal, “Just” People built its own apartment complex. Dowling and her family moved in with her clients.

There are now three “Just” People residential complexes, in Roswell and Lilburn, housing more than 170 disabled adults, plus the day program that attracts more than 100 every day.

The 29,000-square-foot building in Norcross that serves as headquarters for the nonprofit and the community hall for the day program was raucous with fellowship on a recent Wednesday. Decked out with lights, paper snowflakes, a 9-foot Santa statue and at least 10 Christmas trees, it looked like a cheerfully gaudy winter wonderland.

The fun isn’t limited to Christmastime. “Just” People sent 118 athletes to the most recent Special Olympics; clients of the group take a cruise every year. They study ballet and visit museums. Instead of family members feeling that they must account for every moment in the day of a loved one, it allows disabled adults to create their own society.

Clients also learn job skills, and, said Dowling, 90 percent are employed.

“It has literally changed our lives,” said Kevin’s mother, Linda Denslinger, who nominated Becky Dowling to become an Atlanta Journal-Constitution Holiday Hero. “My husband and I are retired, and it has allowed us freedom from worry.”

Dowling, 60, said “Just” People is “just what I do. I don’t it for any reason other than I love it. And these are my friends.”