Dirk was a Hurricane Katrina survivor. Vito's guardian was left unable to care for him after a car crash. Tami was a runaway, roaming the streets of downtown Baltimore when a do-gooder took her to a shelter.
Just a couple of years ago, all three were down on their luck, dogs that, like mine - a stray named Ace who landed in the city shelter - were in need of a hand.
Now all four are lending one.
Ace qualified earlier this summer to become the newest canine member of Karma Dogs - one of several organizations in the Baltimore area, and a burgeoning number nationwide, that are using dogs to teach, train, rehabilitate, heal and comfort.
In addition to the estimated 40,000 "service" dogs assisting people with disabilities in the United States, there are tens of thousands more assisting in smaller ways - helping children overcome reading problems, visiting the elderly and ill in nursing homes and working with people with disorders ranging from autism to Alzheimer's.
As a member of Karma Dogs, a nonprofit organization that uses only "rescued" dogs, Ace has worked in two programs.
At the League for People with Disabilities, he has been part of a program that uses dogs to help connect with, and teach social skills to, people with autism.
And from June until recently, he visited the Towson Public Library every Saturday in what has become an increasingly popular type of program nationwide - one based on the concept that children can improve their reading skills and confidence levels by reading to a warm, accepting, nonjudging, noncorrecting dog.
There are other therapy-dog opportunities in the Baltimore area - including several programs that bring dogs into hospitals, nursing homes and other institutions. In addition to providing a little cheer, time with a dog has been shown to help people with depression, high blood pressure and heart conditions.
I chose Karma Dogs because I liked the name, and the whole "paying it forward" concept, and because it was less expensive than some of the other therapy-dog opportunities I had investigated a year earlier, but not pursued.
It cost $75 to enroll in Karma Dogs; the fee covered the necessary ID tags, Ace's official Karma Dogs bandanna and - the first step - having Ace evaluated by a professional dog trainer.
Liz Hauck, of Drop the Leash, visited my home, had me show her my dog's repertoire of tricks, and put us through some drills aimed at gauging Ace's obedience, which needs work, and his temperament, which is almost always calm and gentle.
From there, we headed to the local park, where Hauck, one of two trainers Karma Dogs contracts with, observed how Ace got along with other dogs.
Except for not coming when I called him a couple of times, he behaved well, was gentle with little dogs that jumped on him and responded to most of Hauck's commands.
A second meeting was set with Hauck at the PetSmart in Towson, which, crowded as it can get on weekends - with dogs and people - would serve as a test to see how Ace reacted to crowds, loud noises and low-level chaos.
There, as Karma Dogs founders Kelly and Andrew Gould looked on, Ace was bumped into with shopping carts, exposed to loud noises like dropped clipboards and nudged in the side a few times to see how he would react.
At one point, at Hauck's instruction, Andrew Gould loudly approached Ace with his arms flailing to make sure Ace would keep a cool head when around people with behavioral issues.
After a good hour in PetSmart, Hauck took Ace outside to chill out, and after a walk around the parking lot pronounced him qualified. (Not all dogs qualify as quickly as Ace did, Hauck said. Some require further training at additional expense.)
There were two more training sessions after that - for me, not Ace - one to review our role in the autism program, another for the library program.
On our first visit to the League for People With Disabilities, we approached several of the program's clients, some of whom wanted nothing to do with a dog as big as Ace.
One teenage boy, though, petted Ace, walked (and ran) him on a leash around the circle in the courtyard several times, then brushed him.
Small as those achievements might seem, they were, for him, progress, Kelly Gould said. With autism, progress is measured in small increments.
"One of the kids I've worked with since January, when I originally met him, wouldn't make eye contact with me or come near the dog," said Gould, who uses her dog, Dirk, in the program.
"But after working with him for about eight months, he's happy to see the dog, greets the dog and hugs me. Before, Dirk and I couldn't hold his attention for 15 seconds; now he will help walk the dog for several minutes at a time."
Using dogs in therapy with the autistic is a relatively new method, Gould said.
"Studies have shown that animals have a way of getting through to people on levels that sometimes other people can't," she said. "With autistic kids, we can help them learn appropriate behavior by using the dog. ... Some autistic children are prone to hitting, grabbing or pushing. If they can learn to pet a dog appropriately, they can learn to be more gentle with humans."
The program at the Towson Library was less intense - at moments even relaxing, for Ace and me.
First we met the other dogs - Dirk, Vito, Tami and Tasha, an older dog who, after spending some time in a medical testing facility, ended up at Animal Rescue Inc. in northern Baltimore County.
Then we went to our assigned window nook, spread out our blanket and waited for readers.
One of the first was Ellen, who is in the second grade. She brought a book from home called My Dog Can. Louise read One Day in Maine, from start to finish, holding Ace's paw through most of it.
Will read a book called Dog and Cat, and stopped to show Ace the pictures. Madeline read a book about the Statue of Liberty, her arm resting on Ace's back.
"If they stumble a little bit, or don't say a word correctly, it's fine not to correct them and just let them go," Gould had said. "The idea is dogs don't criticize or judge them, and they feel more at ease. A lot of times they even forget that a person is there."
Ace spent five Saturdays at the library, had about 20 books read to him, and loved all the attention he received. Gould suspects the dogs' owners get something out of the experience, too.
"I think people love spending time with their dogs, and when you volunteer in this capacity it's really enjoyable to see people's face light up when they see your dog, or to see a kid who doesn't normally enjoy reading starting to enjoy reading because of your dog."
The Karma Dogs program at the Towson Library ended a few weeks ago and a new one starts at the Catonsville Library on Sept. 15.
Gould formed the organization last year. She got the idea for it while working as a volunteer at Pet Rescue of Maryland.
"I wanted to do something long-term that might help dogs and people get along better," said Gould, who works at GKV Communications and makes radio and television advertisements. "The idea of Karma Dogs was to show people that rescued dogs can be more than family pets and can help give back."
Her own dog, Dirk, was a case in point. When the Goulds got a second dog - a blind, 6-year-old named Ernie, Dirk took it upon himself to show the new dog how to get around the house.
"A lot of times, people think rescued dogs are somebody else's problem, or that they were lesser dogs than dogs that came from a breeder," she said.
"That's just not the case."
Dogs on duty
For more information on Karma Dogs, visit karmadogs.org.
Here are some other organizations that prepare people and their pets to visit to institutions such as schools, hospitals and nursing homes:
Pets on Wheels, 410-913-5569, petsonwheels.org
Fidos for Freedom, 410-880-4178, fidosforfreedom.org
National Capital Therapy Dogs Inc., 301-585-6283, visit nctdinc.org
Delta Society, 425-226-7357, deltasociety.org
Dog Ears and Paws, 410-655-2858, www.dogsearsandpaws.com