This year’s suspension of U.S. and European Union sanctions against Myanmar has captured the attention of investors across the globe. Already some of the world’s best-known brands, General Electric and Coca-Cola among them, have made moves to capitalize on a consumer and labor market of about 60 million people and a strategic location between China and India.

Even more promising is what the world’s major oil and gas companies predict will be a vast store of natural resource wealth. That still largely untapped wealth is expected to become the country’s key economic driver going forward.

But while international law firms are eyeing Myanmar as well, hoping to lock up some returns of their own, they say it’s still too early to commit much in the way of resources, much less contemplate a full-scale launch.

“The country just opened,” says Chirachai Okanurak, Bangkok managing partner for Baker & McKenzie. “It’ll take time.”

Baker & McKenzie, Allen & Overy, Mayer Brown JSM, Herbert Smith, Fulbright & Jaworski, Baker Botts, and Rajah & Tann have all begun to serve clients interested in Myanmar, but none have set up an in-country office yet. And so far only Baker & McKenzie has hired a Myanmar-qualified lawyer, Saw Yu Win, who joined the firm’s Bangkok office in August.

There are several reasons for caution. For one thing, a foreign investment law is still in the works. Earlier this month the country’s parliament passed a foreign investment law opening many sectors of the economy, but many politicians are still urging more protectionist policies to favor local industry. President Thein Sein supports liberalization but has so far not signed the bill into law, prompting speculation that another draft may be on the horizon.

Many investors are waiting for clarity on that front, says Simon Makinson, managing partner of Allen & Overy’s Bangkok office. “That [law] seems to be a trigger point for a lot of companies to invest in Myanmar,” he says.

Who to deal with in Myanmar will also be a tough call for potential foreign investors. U.S. sanctions still apply to Myanmar’s military and businesses owned by it. Moreover, many local tycoons who became wealthy through cooperation with the junta are on the U.S. Department of the Treasury’s blacklist of Specially Designated Nationals with whom Americans are barred from doing business.

In April, Reuters profiled one such blacklisted tycoon, Tay Za, pointing out how hard it was for foreigners to avoid dealing with him and his ilk. These “go-to businessmen of the former military junta are now the must-see contacts of Western executives wishing to invest in this former British colony,” Reuters reported.

To top it off, Myanmar is considered one of the most corrupt places on earth. It ranked 180th out of 182 countries on Transparency International’s 2011 corruption perceptions index. Only North Korea and Somalia are ranked lower.

But if there is a reason to rush in, it’s the country’s potential as a producer of oil and gas. Last month an Asian Development Bank report put the country’s proven reserves of natural gas at 7.8 trillion cubic feet and oil at 2.1 billion barrels. There’s a widespread belief that much more remains to be discovered, and international oil companies have been lining up for the right to find it. In August 2011 Myanmar held its largest-ever tender for oil exploration rights, according to Reuters, and nine out of 18 onshore blocks went to foreign companies.

“This is one of the countries in the world that still has undeveloped fields that can still move the dial on big oil and gas [companies],” says Ben Smith, a Hong Kong partner with Fulbright & Jaworski.

Smith notes that it’s easier to move ahead in the oil and gas space because production-sharing contracts — under which oil companies bear the cost of exploration in return for a share of revenues should they find a viable well — are fairly standard across the globe and unlikely to change. This consistency has allowed for a much quicker uptake than other sectors like telecommunications and banking as the country continues to open.

Still, the energy sector is hardly immune to the other issues plaguing the Myanmar economy. According to Reuters, another tender of onshore and offshore oil exploration blocks planned for this month was postponed after a number of Western companies raised questions about the transparency of their potential counterparty, state-owned Myanma Oil and Gas Enterprise. Lawyers in the region say the Western companies may have been influenced by those, including Nobel Peace Prize winner and democracy activist Aung San Suu Kyi, who have recently called for foreign companies to avoid doing business with MOGE, which has close ties to the Myanmar military. In a July statement, U.S. Senators John McCain and Joseph Lieberman likewise expressed concerns about the state-owned company’s potentially unsavory dealings and its lack of transparency.

Andrew MacGeoch, Hong Kong partner at Mayer Brown JSM, says the way forward in Myanmar will not be easy. The country, he says, is “still going to have its ups and downs, bumps and bruises along the way.” He likens the situation to that of Vietnam in the 1990s; others point to China in the 1980s or Mongolia over the past few years.

One advantage that Myanmar may have over those other jurisdictions is the common law legal system left behind by the country’s British colonial rulers when they departed over 60 years ago. But the years of military rule left gaps in the law and the training of lawyers, so there are currently very few local lawyers capable of handling international transactions.

“There are a couple of good firms, but the pool isn’t particularly deep,” Herbert Smith partner Richard Nelson says. Nelson, who heads his firm’s Southeast Asia energy practice in Singapore, points to Myanmar Legal Services and regional tax and legal consultancy DFDL as a couple of the standouts.

The shortage of talent is one reason Baker & McKenzie’s Okanurak says his firm’s strategy is to service clients from Singapore and Bangkok, until an on-the-ground presence is warranted.

The firm will continue recruiting local lawyers, he says, and they will play a major role as Baker & McKenzie expands its footprint in the country formerly known as Burma. Myanmar-qualified personnel like Win will be essential for translation, court appearances, compliance issues and law interpretation, in addition to navigating a largely undeveloped legal system where the gaps between laws on the books and actual practice can be wide.

An update of Myanmar’s laws could take many forms, and could be influenced by the experience of other developing countries in the region, as well as international bodies like the World Bank and Asian Development Bank. But, given Myanmar’s host of issues, MacGeoch is not expecting things to move fast.

“The time frame for doing it will be much longer than most people expect,” he says.