U.S. companies pursuing exploration and development opportunities in foreign countries must consider complex factors in their choices of where to invest. A recent Ernst & Young poll of its leading professionals ranked 10 oil- and gas-rich countries based on economic stability, government structure and accessibility, legal and regulatory systems, oil and gas infrastructure, and the availability of skilled workers. The firm gave each country a green, yellow or red light based on its score. The green light countries-those with favorable conditions for U.S. investment-are Canada, Qatar, the United Arab Emirates, India and Norway. U.S. companies should be able to enter these nations easily and conduct their exploration and development activities successfully, the firm reports. (For more on energy- investment opportunities in the UAE, see the special report in this month's issue.) Canada is a stable and secure country, and increased prices for oil and improved extraction technologies make its tar-sands desirable. Similarly, Qatar's wealth of gas reserves makes it an attractive country, its economy is booming, and it is moving cautiously toward democracy. The UAE, also blessed with abundant resources, pursues moderate foreign policies and is generous with its oil revenues. India, which holds the smallest reserves of the 10 nations in the study, offers a fast-growing economy and a government that encourages direct foreign investment in its energy sector. Norway received the only perfect score in Ernst & Young's poll. This prosperous, progressive nation is richly endowed with many natural resources. Yellow-light nations are China, Saudi Arabia and Russia. These countries have issues with political frameworks, business climates for foreign firms, and workforce problems. Investors should proceed with caution in these countries, as they will encounter various challenges that might impede a project's success, Ernst & Young reports. Countries getting red lights are Nigeria and Indonesia. Companies operating in Nigeria face daunting security issues, a poorly trained workforce, and inconsistent application of rules and regulations concerning the energy business. Indonesia suffers from many economic-development problems, including high unemployment, a fragile banking sector, corruption, poor infrastructure and a weak investment climate. Companies should be extremely cautious about establishing operations in either country, Ernst & Young reports.