The pho restaurants along Buford Highway, halal butcher shops in Clarkston and all the Ethiopian coffee imported directly to south DeKalb County are not foreign developments to county leadership.

Yet the county has been slow to tap into one of the most culturally and ethnically diverse areas in the country to promote foreign business and spark economic development.

"Our job is to see how we can expand on what they are already doing," said County Commissioner Stan Watson, whose district covers eastern DeKalb, a melting pot of immigrant neighborhoods and businesses. "If we can enhance what immigrants are already doing, build into international trade and growth, we'd have an economy like no other."

Officials agree that putting out the welcome mat for new arrivals is the critical first step to encouraging development. But DeKalb has lagged in identifying the makeup of its surge of immigrants and has been mostly hands-off while small businesses like eateries and markets have popped up across the landscape.

A different approach can be found just north of the county line in Gwinnett, which, like DeKalb, has seen its immigrant population swell. Gwinnett has developed a comprehensive plan to lure business from its immigrants’ countries of origin.

In just five years, that strategy has translated into 11,000 jobs created through Partnership Gwinnett, a public-private outreach program designed to encourage investment and spark job growth. DeKalb has no comparable figures available and no formal program in place.

“What makes Gwinnett an ideal local for international business — our diversity, our lower cost of living — is the same for all of metro Atlanta,” said Nick Masino, a senior vice president at the Gwinnett Chamber of Commerce, which oversees Partnership Gwinnett. “DeKalb would be onto something to capitalize on the people already in the community.”

The number of people in metro Atlanta who were born outside the United States has soared in the past two decades and no place more so than in the second- and third-most populous counties in Georgia.

In 1990, the proportion of foreign-born residents in DeKalb and Gwinnett was 7 and 5 percent, respectively, according to U.S. Census figures. Last year, about one in five DeKalb residents was born elsewhere. In Gwinnett, the ratio is one in four.

Both counties have embraced immigrants from some 40 nations, from Pakistan and Taiwan in Asia, to Eritrea and Burundi in Africa, to nearly every Caribbean and South American country. New business owners have found different paths to development.

Gwinnett has sophisticated strategic plans and regular trade meetings with business owners both here and abroad. DeKalb has so far relied on a handful of international festivals to make contacts and used a general focus on science and technology businesses to leverage its diverse population into jobs.

There have been some successes. A focus on boosting small business has created companies like Sam’s Limo Service.

Solomon Berihun started a towncar service with one car a decade ago, after relocating to DeKalb when New York City and Washington, D.C., proved too big and expensive for his dreams.

The Ethiopian native’s business now has seven cars and employs three full time. Business is solid enough that Berihun is pursuing another dream in his spare time: playing the Ethiopian one-string bowed instrument known as a maseinko for parties.

“I chose DeKalb County because you can grow here,” said Berihun, whose home and business are in Stone Mountain. “Everybody is welcome here. This is the place for opportunity.”

The influx of immigrants like Berihun have blurred the historic black-white racial divide of the Old South, creating a New South where African stews are washed down with sweet tea.

But small missteps can turn back years of progress. That’s what happened with Doraville’s quiet decision three years ago to no longer allow wholesale businesses, which were primarily owned by foreign businessmen.

Foreign wholesalers were among the most successful businesses in the city, central suppliers for the region’s markets and also a hub across the Southeast. For the mostly Korean immigrants who ran the stores, to have reached wholesaler status was symbolic of attaining the American Dream.

The lack of understanding that pride led many wholesalers to move out, even if their operations were grandfathered into the new zoning laws. New shopping plazas now line Buford Highway in Gwinnett, with the distinctively round Korean characters in signs advertising the shops.

“I tried so hard to wake people up, to see what was happening,” said Charlene Fang, a Taiwanese immigrant and bank vice president who often serves as an unofficial liaison for the Asian community and DeKalb leaders. “If you lose a wholesaler, it hurts more than one business. It hurts the whole community.”

But even as many Korean immigrants shifted their businesses and homes into Gwinnett, DeKalb sees opportunity in other immigrants moving into the middle class who have chosen to stay.

They are the people creating multi-lingual churches, small mosques and, in the shadow of Northlake Mall, a new Buddhist temple.

The temple was filled to standing-room only at a recent purifying ceremony, with religious leaders from Taiwan present to celebrate the new house of worship.

Anna Kao, the director general of the Taipei Economic and Cultural Office, was among the honored guests. Part of her job is to attract business to the region while also creating more understanding of the estimated 20,000 Taiwanese immigrants, many in DeKalb, who call the area home.

“It starts with an understanding among cultures. Through that, more and more cultures can merge in DeKalb County,” Kao said. “Our countries share the same core language of freedom and democracy and the free market. We have that foundation.”

Staff writer Kelly Guckian contributed to this article.