Lam says his quality of life is much better, now that his coworkers are dogs.
"I was much happier playing with dogs all day than I was going to the office," he said.
And he's not the only one getting in on the dog walking business. According to market research, the dog walking industry rakes in $937 million each year, and that number has been growing steadily over the past five years. Over 21,000 Americans identified as dog walkers in 2013, and some estimates suggest there are around 10,000 pet-sitter businesses nationwide.
Lam feels it's important that dogs get the exercise and attention they need, even when their owners are away.
As for Lam, dogsitting has become a full-time, and financially sound, career.
"When I was at Goldman, I couldn't see myself lasting more than two years. But now, if this is my life for the next 40 years, I wouldn't ever look back and regret it."