Abstract
The mandatory employment clause is a mechanism provided for in the Public Procurement Law (the PPL), the main purpose of which is to promote employment under an employment relationship. It obliges contractors or subcontractors to employ persons performing public procurement contract on the basis of an employment relationship. Under the PPL the contracting authority has to establish appropriate procurement conditions and disclose them in the procurement notice or procurement documents. In order to ensure the effectiveness of this mechanism, the employment obligation must be introduced into the public procurement contract, which additionally must provide for methods of verifying the fulfilment of this obligation by the contractor or subcontractor and sanctions 95for violation of it. The article deals with the question of, among others, normative sources of the employment clause, the legal nature of the employment obligation, possible methods of ensuring the effectiveness of this clause and the effects of introducing the employment clause in the sphere of other solutions relating to the public procurement contract.