International treaties on the limitation of double taxation have set out rules which regulate in which country tax should be paid if taxpayers receive earnings from abroad. This article deals with the place of taxation for gross wages. These taxes are predominantly paid in the country, where the employer has got its registered office. Some rare exceptions exist, however, where the employee reports and pays tax in the country of their origin, i.e. where they have their domicile. This applies to the earnings from employment of Czech boatmen employed in the Kingdom of the Netherlands based on a treaty concluded with the former Czechoslovakia in 1974. The Financial Administration of the Czech Republic has placed many boatmen and their families in a highly unfavourable social situation as a result of demands for the repayment of income tax on earnings from employment, including sanctions, despite the option of a refund of any tax paid in the Netherlands. The objective of this article is to point to a possible conceptual solution for such exceptions.