Bronx: They seem very much like family dogs, and there’s always an extended family. The dogs have cousins. The extended family includes not just your human relatives, but your human relatives’ dogs. So everybody knows everybody. In talking with people, I’ll hear the story not just of their dog, but their sister-in-law’s dog.

Staten Island: They are quieter. They’re a little bit more laid back because they have less chaos around them. They probably have no idea that they live in New York City. It’s very suburban there.

Brooklyn: The dogs that we met were, for the most part, from single-dog homes. Even if they were in a family, it was five people and one dog. And so they seemed to feel a little bit like they were the center of the world. Maybe Brooklyn feels that way about itself, too, these days?

Queens: They are the most diverse. If you look at the pictures that we took in Long Island City of a group of people who meet every morning with their dogs, every dog is completely different. There’s a sheepdog, an Akita, a pit bull, a corgi, a Pekingese, and a Chihuahua. These dogs are all best friends.

What is one of your favorite dog places in the book?

You can go off-leash in Central Park after dark. It seemed like something out of a storybook, and the moon was out and it was reflecting in the water. At first, there weren’t that many other people around, but as we went a little deeper into the park, we started running into more and more people with their dogs. It really was like a secret society because unless you have a dog, you’re probably not going to walk in there.

Did you actually interview the dogs or just their owners?

It was really a little bit of both. Sometimes their owners try to speak for them. But then, if you’re observing, you can see where the dog might disagree. We talked about, where do you want to go? Where do you typically go with your dog? That’s kind of a dog interview, I think, when you walk a neighborhood with a dog and you see where their nose goes.

Your book shows the relationships between dogs and their humans. Is there one that stands out?

Talia is a girl in Queens who is autistic. She has a service dog that’s trained to stay with her. As she is getting older, holding her mother’s hand in public is not a cool thing to do. So now she has this dog to hold on to. I think dogs are anchors in a lot of different ways for all of us. But in this case, it almost seemed like a literal anchor to keep somebody calm and in place.