Read: 12 top international places to retire

Investing in global employees opens up your HR and company to a whole new world — literally — of talent and business opportunities. And since expatriate employees can cost more than three times an individual's yearly compensation, companies have a strong motivation to get it right.

Below are four key strategies for making an employee's transition abroad successful:

Choose the right person

While expat life may seem like a glamour assignment at first glance, rife with adventure and opportunity, not every employee is equipped for life abroad. Employers should be scouting talented individuals months before they ever step foot on a plane — not everyone has the stomach to deal with trials and frustrations that come with life lived away from home.

It is critical to find not only the right person for the job, but the right person for the job that's cross-cultural and far away. For that, you need the right person with the right temperament.

The high performing rule follower may not be the best fit this time around. Is she a flexible thinker? Does he respond well to tense situations? What does she do when outcomes are uncertain? Does he build relationships easily?

Not only do you need to consider your soon-to-be-expat's personality, but you'll need to think through their home life as well. Does he have a family that is willing to relocate? Has she experienced life abroad before?

Does he, realistically, know how tough it can be to live in another country? By fully considering each candidate, including their working style and personal commitments, HR managers can save themselves the headache of repatriating an employee who will be unhappy or unproductive abroad. 

Give employees the tools to succeed

Once HR has supported the process of identifying that special warrior for your company's overseas assignment, the individual process begins.

It doesn't take a rocket scientist to realize that life abroad will be different than life at home, but it will take more than just forwarding helpful books and magazine articles to make sure your employee will thrive.

There's a saying, life is "caught not taught" and this goes for transitioning to new country life. Making sure your employee has a local guide, a bicultural bridge of sorts, will help set them up for success as they help introduce your employee to their new environment.

Legal and cultural differences both play a large part in determining an individual's success, and a counterpart who has familiarity with the host country can steer foreign workers in the right direction.

Outside of a local attaché, companies should also set very clear goals and timelines for employees abroad. What does success look like in their new country? Will this be a permanent assignment, or are expats expected to complete a project, and then return to their domestic lifestyle?

Creating intelligible goals (or for the more freethinkers, clarity around the key problem they are relocating to solve) minus any normal corporate ambiguity helps ensure your employees stay motivated abroad.

Establish a support system abroad

Once you've got the big stuff sorted — when your employee is leaving, living, and duration of their time abroad — it's time to tackle the small details that have a serious impact on an expat's quality of life.

On the human resource side, HR managers should double — and triple! — check that all local laws are being complied with. What is the tax situation like in the new country? How will insurance and other benefits transfer?

These issues must be addressed by HR managers, otherwise a company's employees may find themselves liable to foreign laws or statutes that could put their visa in danger.

Not only this, but making sure there is a steady connection once employees are on the ground — checking in on how they are doing professionally and personally is indispensable to make sure employees have real-time support as they establish themselves in the role. 

A good HR department does scouting ahead of time to help its employee put his or her new everyday life in order. Support via local research on the best expat support groups or bilingual schools for children can help a lot.

Offering resources for low-cost international money transfers is a great thing when the country has a different currency. Sharing the best apps for navigating new cities as well such as Trainline for public transportation, Citymapper for navigating the city, or Duolingo for language is also helpful.   

Don't ignore re-entry shock

Working abroad can absolutely be the adventure of a lifetime. Employees can hone their business acumen, make exotic new contacts in key countries, and expand their own personal horizons. It's no surprise, then, that "reverse culture shock" can present very real problems when expats begin to re-integrate into their home country.

Psychology experts have pinpointed the three main points returning expats must grapple with: their home has changed; they have changed; they have adapted to another culture and now they must readapt. This three-pronged adaptation may seem simple on the surface, but it can present a real problem to returning employees.

To combat this, it is wise for HR managers to reach out to employees as they return to their home countries, ensuring their "off boarding" process is as rigorous as their original expat onboarding process and also support managers to be doing the same.

Just as your HR department probably helped your employee to find a bridge between the new culture and home country, they can now be the bridge between the returned expat and domestic employees.

HR can help by creating forums where returning workers share their newly-acquired foreign knowledge with their home base counterparts — spreading the worldly knowledge and cultural quirks can be fun too.

You will end up not only creating an environment where everyone in the company can benefit from your employee's time abroad, but you'll also create interest in other positions posted far away from home.