Q. When did you realize that Marley's escapades might make for fun reading?

A. Pretty early on, actually. Within weeks we were recounting his antics at dinner parties, and I began trotting him out in my newspaper columns shortly thereafter.

Q. Why was Marley so lovable despite being such a pain in the neck?

A. I think it had something to do with his guileless heart and over-the-top zest for life. Just as he was incapable of putting the brakes on his behavior, he had no bounds on his affection and loyalty, either. Not necessarily a bad thing.

Q. Were there any Marley "stories" that didn't make the book?

A. Oh yes, lots. What can I say? The dog was a wealth of material. Here's one: One day I was installing a new window in the house, and I had a bowl full of sheet-metal screws sitting on the ground. Marley charged over, snuffled his nose into the bowl as though they were candies, and trotted off. A second earlier I had 24 screws; now there were 23. Sure enough, within minutes Marley was retching and heaving. We rushed him to the animal hospital, imagining the sharp screw shredding his insides. Two hundred dollars worth of x-rays later, Marley was feeling fine and bouncing off the walls. We never did locate the missing screw, either in or out of him. There are many stories like that.

Q. What would Marley's reaction be to the book?

A. I'm pretty sure he would have eaten the manuscript by now. And left no trace.

Q. At what point did the story become about more than just a dog?

A. That's an interesting question. I began writing this book just a month or so after his death, and I was learning as I was going. It was a bit of a process of discovery for me. Quickly I realized I couldn't tell Marley's story without telling the story of my wife and me and our intrepid journey into parenthood. Eventually I realized my book was not so much a "dog book" as the story of a family in the making and the bigger-than-life animal that helped shape it.

Q. Was it difficult to relive Marley's life so soon after having lost him?

A. Actually, it was therapeutic. Cathartic. I would read passages aloud to my children as I progressed, and it seemed to help them, too. Mostly we laughed. Bittersweet is probably the right word.

Q. You end the book with you and your wife heading out to look at a shelter dog, a Marley clone named Lucky. Did you end up adopting him?

A. Lucky was a sad story. When we showed up to meet him, the staff took one look at our young children and told us they would not let us adopt Lucky. He had been seriously abused and was just too unpredictable to be around kids. He had a wide host of issues that made Marley look downright well-adjusted by comparison. The good news is Lucky was at one of those well-endowed, fairly luxurious private shelters with a no-kill policy. So his worst-case scenario will be living out his years there surrounded by an attentive staff.

Q. Did you ever get another dog?

A. Nine months after Marley's death, we brought home a beautiful female yellow Labrador retriever puppy. Gracie is smart, calm, easily trained – and just a little boring. But then after Marley, probably any dog would be.

Q. Are you working on anything new?

A. Oh, yes, absolutely. But I'm not quite ready to talk about it. I'm a little superstitious that way.

Q. What's the hardest aspect of writing?

A. The only difficulty is that little part that involves putting words on a blank screen. Other than that, it's a breeze! Seriously, I have little tricks to avoid writer's block. One of them is to create the "official document," which seems very intimidating and sits blank. Then I create a "rough notes" file, which I write in. Since it's meant to be rough – after all, that's the name of the document! – and no one will ever see it, I don't worry about what spills out of me. After I get down a chunk, I let it sit overnight and then go back and work it over. Usually, about 90 percent of it gets used. It's a ridiculous little game, I know, but it helps me. I also keep a faithful journal, which is another great tool.

Q. Do you have any special writing routine?

A. I'm usually a night owl, but when I wrote "Marley & Me," I forced myself to go to bed early and get up early. I wrote from 5 to 7 a.m. and then ate breakfast and went to work to write my newspaper column. I averaged a chapter a week this way. I began the book in early 2004 and finished the manuscript right after Labor Day. My agent, Laurie Abkemeier, sold it the next month in an auction.

Q. What advice do you have for writers?

A. Take the Civil Service exam and hope for a job at the Post Office. No, no, no. Keep a journal and write every day, even when it seems impossible. Read really good writers, and re-read the best parts aloud. Write about what you know and care about. Believe in yourself and your voice. And here's what I consider the most important part: Take your finished piece and cut it by 20 percent. Relax, you can always restore the lost text. You'll be surprised how seldom you will feel the need. In my own work, tighter is almost always better.

Q. Who are some of your favorite authors?

A. Gosh, where to begin? I love everything Bill Bryson has done, especially "A Walk in the Woods." I was deeply moved by Alice Sebold's "The Lovely Bones." Frank McCourt's first-person voice and uncompromised honesty inspired my writing. I'm a fan of Jim Harrison's. Also John Irving, E.B. White, Anna Quindlen, Charles Frazier, David Sedaris, Donna Tartt, and just for plain fun, Dave Barry. In the love-hate debate over Hemingway, I'm in the love camp.

Q. You wrote a column in The Philadelphia Inquirer about Marley after his death. Did that play a role in your decision to write a book?

A. Very much so. All through Marley's life, I entertained friends and readers at his expense, trotting him out to tell stories about his hopelessly bad behaviour. After he died, I figured I owed it to him to tell the rest of the story, the whole story. Yes, he was an attention-deficit, hyperactive, nutty dog, but he had a pure heart and an incredible gift of canine-human empathy. The day the column ran, nearly 800 Inquirer readers emailed or called. A typical day might bring 30 to 50 responses. That's when I knew I had a bigger story to tell.

Q. Are your children jealous of your close relationship with your dog?

A. Quite the contrary, they consider our pets special members of the family and their own best friends. They were bereft when Marley died. My wife and I lost a beloved pet, but for them it was like saying goodbye to a sibling. He had been close beside them every step of the way, from infancy forward – drooling all over them. A dog is the greatest gift a parent can give a child. OK, a good education, then a dog.

Q. Isn't it a little frivolous to spend this much time and energy discussing a dog when there are so many problems in the world? Why are dogs important enough to write about?

A. I have this theory, and writing the book sharpened it, that people can learn a lot from their dogs. Lessons on how to lead happier, more fulfilling lives. Lessons for successful relationships. Think about it. Many of the qualities that come so effortlessly to dogs – loyalty, devotion, selflessness, unflagging optimism, unqualified love – can be elusive to humans. My hunch is that people who act more like dogs have happier marriages. That's assuming, of course, you don't marry someone who emulates cats. Then you're in trouble. Cats will outsmart dogs every time.

Q. It's interesting you say that. You and your wife brought Marley home just as you were starting out in your marriage.

A. Right. People get dogs at different points in their life, and Jenny and I both had grown up with dogs. But Marley came into our lives right at that special juncture when we were attempting to meld two individual lives into one shared relationship. Marley, in all his goofy glory, became inextricably woven into the fabric of what became us. I write that in the book. He came into our lives just as we were figuring out what those lives would be, and I do think he helped shape us as a couple even as we tried to mold him to our will.

Q. What was the biggest lesson you took away from your relationship with Marley?

A. That commitment matters. That "in good times and bad, in sickness and in health" really means something. We didn't give up on Marley when it would have been easy to, and in the end he came through and proved himself a great and memorable pet.

Q. So he's not really "the world's worst dog"?

A. Nah.