This article discusses the issue of the employer's obligation to cooperate with public authorities in the case of collective redundancies, which is a means of social protection of employment relationships. The author first explains the concept of social protection of workplaces, pointing out that one of its instruments is the obligation to notify the competent employment authorities of the intended collective redundancy. Furthermore, the paper analyses the regulations of abovementioned employer's obligation under ILO Law (Convention No. 158) and the European Union Law (Directive 98/59/EC). Thereafter, the author discusses the relevant regulations contained in the Act of March 13, 2013 on specific terms and conditions for terminating employment relationships with employees for reasons not related to the employees, subjecting above mentioned regulations to critical analysis and examining whether the adopted manner of regulating this obligation allows it to be an eff ective, proactive means of social protection of employment.