The subject of the research presented herein is the relationship between the national parliaments (NP) and the institutions of the European Union (EU). The main objective of the analysis is to examine their nature, existing relationships and processes, as well
as determining their dynamics and intensity. In addition, the impact of these interactions on the EU political processes and the effects on the functioning of the EU system will be assessed. Recent regulatory changes have expanded the scope of cooperation between NPs with the EP, the Council and the European Commission and the ability to
influence political processes of the EU. In practice, the relationships between the NPs and the EU institutions are complex and self-organised and have significant impact on the political processes of the EU. For this reason, the study used the concept of policy
networks.
My hypothesis is, that the varied and complex forms of cooperation between the NPs and the EU institutions developed through good practices and self-organisation are a policy network and have positive influence on the political processes of the EU. Networks allow to transfer the national experience to the international and transnational arena. This is an important and current research
problem in the context of the debate on reforming the EU.