If your company sends employees on extended assignments in other countries, there are several steps you can take to help improve the chances of success in a venture that can be extremely costly if it fails.

Over the course of a typical three-year stay, the cost of an international assignment can exceed $1 million, according to the National Foreign Trade Council.

The failure rate averages about 50 percent, with the highest failure rates in India, China and Russia, respectively, according to a recent global relocation trends survey by Brookfield Global Relocation Services.

China is also the No. 1 destination of international assignments.

Yet the number of Americans being posted abroad is growing. The reasons are simple – companies are looking for larger markets for their products and seeking cheaper production costs.

This globalization of business is making it more important than ever for companies to learn how to successfully manage their employees who are assigned internationally.

Here is some advice for improving the chances of success.

Select the right people for the assignment

Too often, selections for international assignments are made for the wrong reasons. They may be:

• A perk, where the location is desirable and the employee wants to go
• Part of the company’s career ladder that is seen as grooming managers for more senior leadership
• A move for a manager who has been successful in one location to take over in an international setting

Instead, you should assess whether candidates – and their family members – are a good fit for the post. You need to consider candidates’ job-related competencies, personality traits and family circumstances.

Important skills and personality traits for international assignments include:

• Self-confidence, self-reliance and ability to work independently
• Willingness and ability to learn the language of the host country
• Perseverance and resilience in the face of obstacles
• Flexibility and the ability to deal with ambiguity
• Tolerance and respect for people and customs that seem strange or unfamiliar

Don’t overlook the importance of family. Issues with family are the main reason for failed assignments.

Consider whether the spouse and older children will be able to adjust. Younger children generally do better than older ones. Does the spouse expect to find work in his or her career field in the host country? Only a small number are able to do so, and this often becomes a source of dissatisfaction for them.

Help the employee and family prepare before departure

Proper preparation can make the difference in the employee’s and the family’s adjustment to the host country and the ultimate success of an international assignment.

If the host country is not English-speaking, provide mandatory cross-cultural and language training. Most companies offer this, but few make it mandatory. And it needs to be.

Some culture shock is probably inevitable. But preparation can lessen it. There are vendors that provide this service.

Online expatriate “chat rooms” dedicated to the specific country can provide mutual support before and during the assignment.

Address family concerns with the employee and the spouse. Help them to be realistic about such things as the spouse’s chances of finding suitable work. Provide assistance with logistics, such as finding a house and schools.

Providing the employee and the employee’s family with a knowledgeable host-country guide or assistant is enormously helpful.

This person can be part of the preparation phase – by telephone or email – and a source of local support during the assignment. Needless to say, the guide should be bilingual.

Continue to provide support while on assignment

Keep in frequent communication with employees who move abroad. Include them in meetings via telephone or the Internet and keep them in the loop on developments that concern them.

Ask employees living abroad how they and their families are doing and if there is anything they need. Monitor their work performance. These steps allow you to arrange help or intervene before problems grow too large.

Continue the host-country guide and advise employees about any local, face-to-face support groups for American expats. If there isn’t one currently, your company could sponsor one.

Finally, consider offering an international EAP (employee assistance program). These can assist with child care, schools, counseling, legal questions and more. If you have a domestic EAP, it may offer this service. If not, ask your healthcare vendor or check the marketplace.

Assist in repatriation after the assignment

In 2010, 38 percent of expatriates left the company within a year of coming home from abroad – some voluntarily and some not, according to the Brookfield survey. The 15-year average is 22 percent.

This high rate is most often caused by there not being an appropriate position available when the employee returns.

Other sources of dissatisfaction include moving from a position of more authority and independence to less, and changing from being a “big fish in a small pond” to being a “small fish in a big pond.”

Preparation for repatriation should begin in the pre-assignment preparation phase. This should include discussions of post-assignment expectations and the impact on their career. Cross-cultural training is also helpful when coming back to the United States.