The non-compete obligation of the employee during the employment relationship is an aspect of the duty of loyalty. Although the Turkish Code of Obligations No. 6098 regulates the non-compete obligation, it would be appropriate to interpret this regulation in compliance with the Constitution in order to determine the scope and limits of it. The same interpretation method is also valid if the non-compete obligation is regulated by contracts. Accordingly, considering that a condition stipulated in an individual or a collective labor agreement regarding the non-compete obligation is to be regarded as an interference in the employee’s freedom of contract, one has to take into consideration the possibility of invalidity of the condition cited above. Furthermore, the negative effect of the side jobs undertaken by the employee in his spare time should not fall under the duty of loyalty. Rather, the adverse effects of the side jobs on the primary job can be handled within the framework of bad performance. This argument is also in compliance with the employee's personality rights, the principle of good faith and constitutional guarantees. Likewise, preparations for competition are also outside the scope of non-compete obligations. Accordingly, acts of preparation for competition, including the establishment of a competitor, but non-functioning company, should not be considered contrary to the non-compete obligation.