Mongolia’s natural resources weren’t exploited during the decades that it was a Soviet client state—Russia treated the country as a buffer against China, and little else. But Mongolia is finally starting to profit from its vast mineral wealth, and international firms are eager to join in the boom.

Two Australian firms, Minter Ellison and Allens, opened offices in the capital city of Ulaanbaatar earlier this year. DLA Piper launched a formal association with a local firm last year, while U.K. firm Clyde & Co sealed a similar tie-up this March. More global firms are likely to arrive soon, but they’ll face two obstacles: a dearth of suitable local firms to partner with, and a shortage of international lawyers willing to relocate to the cold and remote country.

Mongolia’s economy expanded by more than 17 percent last year, far outstripping China’s rate of growth. The country sits on huge deposits of gold, copper, iron ore, uranium, and coal. The biggest project so far is the development of the Oyu Tolgoi copper and gold mine. Canada’s Ivanhoe Mines Ltd. owns a 66 percent stake in a joint venture with the Mongolian government to develop the mine. Ivanhoe, which is 51 percent owned by Anglo-Australian mining giant Rio Tinto, has poured more than $5 billion into the project.

Allens helped Rio Tinto negotiate its position in the Oyu Tolgoi joint venture. “If that comes off as it’s expected to, it will underpin the entire economy,” says Erin Feros, a Brisbane-based partner with the firm. Feros says that Allens doesn’t intend to have somebody in its Ulaanbaatar office full-time—instead, she and other lawyers, including Hong Kong partner David Wenger, will rotate in and out of the branch.

Of the international firms in Mongolia, only Minter Ellison and Hogan Lovells have full-time partners in the country. Minter partner Elisabeth Ellis, who relocated to Ulaanbaatar from Hong Kong in February, says it can be a daunting place. Temperatures plunge to minus 10 degrees or lower in winter. The city is choked with traffic, there’s a shortage of hotels and restaurants, and Internet access can cut out at any moment.

But Ellis, a 43-year-old self-described “Mongolia convert,” says the thrill of the country’s rapid development was enough to entice her. She visited the country 10 times over the past two years before moving to Ulaanbaatar with her husband and three young sons. “I am excited about being somewhere that it is in the midst of such incredible growth,” Ellis says. “I was adamant that I could only really be a part of it if I was on the ground.” Minter has advised the Oyu Tolgoi joint venture on a power purchase agreement and obtaining transmission equipment. Ellis is also acting for foreign resources companies on obtaining licenses for coal bed methane projects and other deals.

Hogan Lovells has its own frontier lawyer, too. In 2009, four years after Michael Aldrich joined the former Lovells in Beijing as a partner, Mongolian law firm GTs Advocates invited him to Ulaanbaatar on a paid secondment. “At that time it was very much a black box. No one had any idea what would become of Mongolia,” he recalls. Hogan Lovells has since set up a full branch in Ulaanbaatar, headed by Aldrich. Together with Norton Rose, the firm is advising the state-owned company that’s the sole owner of the Tavan Tolgoi coal mine on a planned $3 billion initial public offering. Tavan Tolgoi, in the Gobi desert, already measures as the world’s largest coking coal deposit, with 6.4 billion tons.

Aldrich’s presence in Ulaanbaatar isn’t driven by business, or even necessarily law. An author of books on Chinese and Mongolian culture, he says he fell in love with Mongolia’s rarely discussed charms—from its world-class opera house to its open-minded people. However, he admits that it’s not for everyone. “You need people who are going to be pioneers,” says Aldrich, who’s been joined in Ulaanbaatar by a second Hogan Lovells partner, Russia specialist Chris Melville.

One challenge is communication. Minter’s Ellis is learning Mongolian—a language that shares its roots with Turkish but is written in Cyrillic, like Russian—but says she’s unlikely to ever speak it at a professional level. While most businesspeople speak English, meetings with government officials are in Mongolian, which requires interpreters. The lack of local legal translators is “a never-ending problem,” adds Aldrich, who has recruited a U.S. student of Mongolian linguistics to join the firm in Ulaanbaatar.

Not everyone feels the draw. Milbank, Tweed, Hadley & McCloy has advised on a host of Mongolian deals, including Mongolian Mining Corp.’s buyout last year of rival miner QGX Coal Ltd., a deal valued at up to $950 million. But Anthony Root, the firm’s Asia managing partner, says it has no plans to set up in Ulaanbaatar. “For a Wall Street law firm, it’s difficult to justify the complexity and expense of having an office there,” Root says.

Last year Gibson, Dunn & Crutcher was invited by the Mongolian Stock Exchange to advise it on a partnership with the London Stock Exchange in preparation for the Tavan Tolgoi listing. But no Ulaanbaatar office is planned. “Gibson Dunn does not move rapidly into new markets if we can service them from elsewhere,” says Singapore partner John Viverito, who leads the firm’s Mongolia work. But he can see why some others would: “For those firms that get in early, the rewards will be great.”

Like Hogan Lovells, DLA Piper decided to expand into Mongolia by teaming up with a local firm, C&G Partners. Though DLA Piper’s relationship with two-partner C&G is nonexclusive, eventually it will become a DLA affiliate firm or even a full branch, says Paul Lee, a Hong Kong–based DLA partner. Lee says that it can be a challenge to find someone “suitable and willing” to transfer to Ulaanbaatar. DLA partner Stewart Diana fits that mold: Though based in Singapore, Diana spends most of his time in Ulaanbaatar, says Lee.

Lawyers like Ellis and Aldrich say that it’s inevitable that others will follow them into Mongolia soon. “The thing that struck me on my visits over the past 12 months is the rapid change,” says Feros. “There’s something new every time you go.” And that includes law firms.