During the last eight years, James Sheldon* has served his Uncle Sam in Athens, Tokyo, and the Sinai Desert. And he did not even have to go through basic training. Sheldon was working as a foreign service officer for the U.S. Department of State.

Foreign service officers are America's diplomacy corps. They typically are generalists who perform a multitude of duties across the globe - issuing visas, protecting U.S. citizens overseas, accompanying foreign officials, reporting on diplomatic issues, and conducting press conferences for ambassadors. Foreign service officers are classified into five functional areas of specialization, or "cones": political, economic, consular, administration, and public diplomacy.

Sheldon, 38, was a banker for several years but switched careers after observing embassy life. "When I was in grad school, my father got a job at the Agency of International Development and was posted in Cairo. When I visited in my late 20s, it was my first exposure to embassy life. That's how I got interested."

Many foreign service officers choose this as their second or third career, and the average starting age is about 30. Officers must also be a U.S. citizen, at least 20 years old, no older than 59, and available for worldwide service. But that is only the beginning.

Each year the State Department offers a written aptitude test that, according to the State Department's website, "measures a candidate's knowledge and understanding of a range of subjects determined by a job analysis to be important to perform the tasks required of a Foreign Service officer."

About 30 percent of test takers are invited for an oral assessment, which consists of exercises designed to test both skills and behavior, such as communication, the ability to work with others, leadership, judgment, and objectivity. If a candidate passes this portion, he or she is still subject to a security and background check. If everything checks out, the candidate is offered a position and enters the Foreign Service Institute, the State Department school for diplomats, for training that can last up to nine months.

Officers serve tours that last two to four years, usually overseas. According to Sheldon, the first tour is almost always served overseas and is generally in a foreign embassy or consulate. About 90 percent of second tours are also abroad. One of the first four years of service must be in consulate work, because the demand is so high. After four years, professionals who now have more tenure can become mid-level officers, working on more sophisticated, more important issues.

Sheldon spent his first tour in Athens, Greece, and moved to Tokyo for his second tour. His third tour took him to the Sinai Desert, where he monitored the peace treaty between Egypt and Israel with the International Peacekeeping Force.

An officer needs to be flexible. "Not everyone can go to Paris, London, and Rome," said Sheldon. "When you sign up, you must sign a statement that you accept the needs of the service. You may want to go to Paris, but they may need a French speaker in Haiti."

The lure of new cultures and challenges is enticing to many, though. "I got to change jobs every two to four years and work on a variety of issues," Sheldon said. "I went to Tokyo, which has millions of people, to a military camp with a thousand ... [The job] is an opportunity to live and interact with people overseas and experience new cultures and other people in a way tourists can't," he said.

"It offers an unparalleled opportunity for someone to assume significant responsibilities, and it is an opportunity to serve your country overseas," he added.

There are down sides associated with the job. There have been attacks on U.S. embassies, and there are posts where health conditions are poor. In certain volatile regions, such Bogota, Colombia, and Beirut, Lebanon, a family cannot accompany an officer. Danger and hardship pay attempts to compensate for such sacrifices.

Some candidates may find the U.S. State Department to be unresponsive to the needs of dual-career couples, Sheldon said. The State Department, he said, is similar to the military, and a candidate must be prepared for its bureaucracy and its hierarchy.

Strong candidates generally have a knowledge of history, government, political systems, cultures, world geography, international affairs, and political and social issues across the world. Basic accounting, statistics, management, interpersonal communication, and knowledge of basic economic principles and trends are also important skills.

Someone with a BA can anticipate a starting salary around $30,000, and the pay structure is similar to that in other government organizations. Senior foreign service officials can make over $100,000 per year.

Being a foreign service officer is not for everyone. When Sheldon became engaged to be married, he resigned from the foreign service. The life of an officer can be difficult for families. "My fiancée is an attorney and can't practice overseas," he said. "If I have to move every three to four years, it would be an incredible burden," he said.

So, if your lifestyle is flexible, and if you want to travel the world, experience new cultures, and serve your country, consider a career in the foreign service...and dream on!

*Not his real name.

- Zachary Bromer, Salary.com Contributor