Jonathan Mervis, right, vice president of business development for Mervis Diamond Importers, with his father, Ronnie Mervis, chief executive, at their location on K Street NW. (Evy Mages/FOR THE WASHINGTON POST)

The best thing about Washington, Jonathan Mervis says, is that thousands of young professionals flock to the area every year — “and they all happen to be at the perfect age to get married.”

As someone who sells engagement rings, Mervis relies on that steady stream of newcomers to keep his family’s 79-year-old company thriving.

The nature of his business creates a set of unique challenges: There are few repeat customers, and the folks who do come into one of the company’s three stores are usually quite clueless.

“All they know when they move here is ‘Every kiss begins with Kay,’” said Mervis, vice president of business development for Tysons Corner-based Mervis Diamond Importers. “The challenge becomes, how do I get the guy who just got here from Seattle to hear about us?”

Mervis has decided on a solution that is part word-of-mouth, part education and part Internet marketing. The company created a series of informational videos and has begun using “retargeting,” those Internet ads that follow you around long after you’ve checked out a certain item online.

“Nobody just wakes up and says, ‘I’m going to buy a diamond,’ and gets it that afternoon,” said Mervis, 30. “Retargeting is a way to remind them, ‘Hey, weren’t you going to buy a diamond?’”

Most of the company’s ads are set to appear on a particular user’s computer for 30 days following their last visit to

It seems to be working. Annual revenue rose by double digits last year, and Mervis said the company is on track to make similar gains this year. He declined to provide figures.

The company, founded in 1935, currently has three locations: Tysons Corner, Rockville and on K Street NW.

A few years ago, Mervis began posting educational videos on its Web site, including titles such as “How to buy a diamond” and “What if she doesn’t like it?” The idea, Mervis said, was to get first-time buyers to think of the company as an authority that could guide them on their hunt.

The average visitor now watches more than 12 minutes of video on the company’s site, Mervis said.

Along the way, he has come up with his own formula for gauging progress: What percentage of Internet visitors created a wish list? How many looked at the stores and hours page?

“If they make an appointment on the site, that, to me, is a home run,” he said.

It’s also a home run for the company behind the latest retargeting effort: Falls Church-based HubShout. The firm, founded in 2008 with two employees, has grown into a 50-person enterprise. Last year, revenue rose 68 percent to $4.2 million.

“For a lot of small businesses, this is the first time they’ve been able to pinpoint the audience that will respond to their ads,” co-founder Chad Hill said.

More than 140 local companies now rely on the service to woo customers.

At Mervis, where the average engagement ring sells for $8,700, persistent marketing is key.

“For the past 25 years, we’ve had the exact same radio ad voiced by the exact same person,” Mervis said. “Now we’re just moving that online.”