Application of Art. 15 OECD MC very often leads to numerous number of unsolved interpretation problems. Art. 15 (2) c definitely is the one which increases the level of uncertainty for employee and leads even to double taxation of the same revenues. In such a case the interpretation problem is not only related to the meaning of particular provisions of Art. 15, but also to the meaning of „permanent establishment“ and/or problems related to relevance of the remuneration for that PE. It would be advisable for OECD Fiscal Committee and/or respective tax authorities to take into consideration a simplification of that provisions. This is extremely important due to the fact, that taxpayers in such a case are individuals. A huge increase of cross border movement of labor forces results in the increase of number of cases related to double taxation of their income. Furthermore very often it is technically difficult and expensive to fulfill all local requirements related to taxes due . The above analysis leads to the conclusion that salaries paid by permanent establishment should be taxable in the state of residence of the taxpayer. On the other hand, PE should not be able to deduct its costs as a tax deductible costs of PE. This construction could simplify tax calculations of individuals employed by PEs and allows countries where the work is performed to benefit from a such by the increase of taxable base of PE as a such not by charging individuals with this taxes. Furthermore, from the perspective of fiscal administrations it is always much more easy to tax and control if such a taxation is complied with all the regulation than to tax employees who even can not be able to pay such taxes in a proper way.