Streszczenie
Internationalization of activities is in fact every day action not only corporations, but also medium and small enterprises. There are a lot of reasons why companies decide to internationalize. However, no matter what the reason for the activity is one thing is certain that simultaneously with internationalization the pool of managers working internationally increases. Nevertheless, managing the group of employees is not easy. Mistakes made while managing the employees can result in failure of an international business mission. Taking that into consideration the objective of the paper is to underline key determinants of expatriates’ performance.