As a teenager in the 1960s, Rita Goldberg was a favorite to make the British Olympic swim team when an injury ended her career. She drifted away from the pool and eventually started a family in Manchester. But when her children were old enough to attend school, she found herself with free time. That’s when one of her former coaches invited her to come see a swim school at his country house outside the city.

“It was my lifetime’s light switch,” Goldberg says. “This older man just loved to teach. And I was just a housewife without a job who was never interested in business. But after seeing that school, I knew what I wanted to do.”

Soon she started her own swim school. Her husband had been struggling in his business and was ready for a change, too, so the couple sold their house and bought a derelict old Victorian with a huge basement, where they installed a pool. It was a gamble, but by the first day in operation in 1981, they booked 100 lessons. Goldberg’s now ex-husband still runs the pool, which is full of novice swimmers daily from 9 a.m. to 9 p.m.

But Goldberg was a more restless soul. In 1992 she relocated to the States, partnered with a pair of American entrepreneurs and opened an indoor swim school in Florida, eventually building three more. Over time she developed her own curriculum, and most important, focused on a method of teaching babies to flip over in water to prevent drowning.

While her schools were successful, she was tired of the partnership and the expense of building pools. That’s when she had an idea.

“If you go into any big gym, almost all the equipment is being used all the time. But the pools are almost always empty. Hotel pools are the same way. It seemed like a ridiculous waste of money to me,” she says. “I started to look at the possibility of partnering with places that had indoor pool space.”

She signed a contract with Bally Total Fitness and sent seasoned teachers to run classes at two locations in Florida. When Bally asked her to open locations in Washington, D.C., and Westchester County, N.Y., however, the schools proved too difficult to manage.

“We could find plenty of pupils. I just couldn’t find the right people to run the schools,” she says. “They kept coming and leaving. Something was missing. I realized I needed someone who’s really a part of the business. That’s the route that took me to franchising.”

In 2011, in her early 60s, Goldberg began franchising. To date, her British Swim School has sold 28 locations in nine states and recently had its first franchisee reach the $1 million revenue mark. Though it offers a full range of classes for all age groups, the system’s primary focus is on teaching children from 3 months to 9 years old.

In the beginning, most of her franchisees were current or former teachers who were looking for a way to make a living in aquatics. But now Goldberg is signing up more experienced businesspeople. “What I try to explain is, swimming is our product,” she says. “You don’t have to be able to teach it in order to sell it.”

British Swim School has barely dipped its toe in the water but is anticipating major growth from a pending partnership with a major fitness brand with 650 pools that can host Goldberg’s lessons. (She won’t name the brand until the deal is finalized.) She expects the relationship to allow her to market to multi-unit franchisees.

“I never expected this brand to do as well as it’s done, but I’m absolutely thrilled with the way it’s working,” she says. “People say it’s a brilliant idea. I tell them I really don’t know how this all happened!”