Julie Azuma, founder of online retailer Different Roads to Learning, talks quietly with her two employees in DRL's Manhattan office. As befits a company that has tripled its revenue in the past five years, the atmosphere is purposeful. That is, until a delivery arrives and Mookie goes wild. But you can't blame Azuma's wheaten terrier for resenting the intrusion. Azuma's business is in her home -- and as much a product of her heart as her smarts.

Back in 1994, Azuma learned that her daughter Miranda was severely autistic, following several heartbreaking years in which specialists failed to explain her obvious developmental delays. Already six when diagnosed, Miranda wasn't talking. Azuma and her husband turned to applied behavior analysis (ABA), a now prominent but then little-known method for teaching language and social skills to autistic kids. Through ABA, Miranda learned to communicate basic needs.

Azuma was sold on ABA, but it was nearly impossible to find appropriate flash cards and other educational tools. Azuma, who had previously worked in the fashion industry, saw an opportunity to start a business to help other families while working at home, close to Miranda and a younger daughter, Sophie. She scoured stores and catalogs for suitable materials, purchasing samples and tracking down distributors all over the world. Soon, she had created an online store stocking 30 ABA products. "I thought I'd make $30,000 a year," Azuma recalls.

Ten years later, DRL offers 250 items to a customer base of 22,000. Sales by DRL and a newer publishing arm, DRL Books, totaled $1.7 million last year. Azuma's formula is simple: personal attention to her customers, many of whom are parents who seek her advice and support as they face the challenges of raising autistic children. She also addresses the practical end, with services like lightning-fast delivery. Proponents of ABA believe that it is most effective when children are very young, so "parents of autistic kids want it immediately," she says. Mary Howley, a New Jersey mom whose daughter Kathy is autistic, raves about DRL's service. "There were many times when my package appeared at my door less than 24 hours after ordering," she says. "When I found out that the owner was a mom facing the same issues I was facing, I thought, 'No wonder."

For a long time, Azuma and her staff handled fulfillment themselves. "We loved touching everything," she says. Last year, the business added so many new products, however, that Azuma reluctantly had to farm out that function. So far she has been happy with the arrangement.

With energy to spare, Azuma is poised for a new venture, which began when a doctor friend suggested extending her business to Alzheimer's. "I told him to go away," Azuma laughs. But the idea stuck, and this year she'll launch a line of "age-appropriate" memory aids. She unveils some samples: large-piece puzzles of screen legends such as Humphrey Bogart and Katharine Hepburn. She also serves as the chair of the group Asian Women in Business, which she helped found.

In 2002, Miranda moved from the apartment to a nearby ABA-based group home. Though she has yet to reach many of the milestones her parents hoped for at first, she continues to make progress. With Miranda always in her thoughts, Azuma says she finds her work "cathartic," especially when customers' young children experience breakthroughs. "It's not just selling them something," she says. "It's sharing their problems and their triumphs."

Wendy Fried