For 23 years, Dr. Jim Withers has been doing street rounds in Pittsburgh, Pennsylvania, bringing medical care to the homeless.
Krisanne Johnson for CNN
When he started in 1992, he dressed like a homeless person in order to connect with the men and women who had been excluded from his care. "I was actually really shocked how ill people were on the street. It was like going to a third-world country," Withers said.
KRISANNE JOHNSON for CNN
Withers' one-man mission has since expanded to a citywide program called Operation Safety Net that includes a mobile van, drop-in centers and a primary health clinic, all where the homeless can access medical care. The group also does home visits to people who have transitioned off the streets.