This article examines the rules for determining an objectively applicable law, namely habitual place of work and the engaging place of business and escape clause according to Rome I Regulation. Situations when the employee is temporarily employed in another country and international transport workers (seafarers, drivers, personnel working on board aircraft etc.) who have a base in a particular country are also revised. The base rule indicated in Rome I Regulation permits the identification of the habitual place of work for permanent international workers. The registration of the aircraft and the flag of the ship are not indicated in Rome I Regulation as connecting factors. The criterion of a place of employment laid down in Rome I suggest that even those workers who ordinarily work in more than one state have a normal place of work. This means that the place of business criterion for employing an employee will be applied very rarely. The escape clause applies only when the question of the law applicable to the employment contract has been assessed through the prism of the habitual place of work or the place of employment.