The course aims to introduce students to fundamental mechanisms of contemporary international law, providing basic knowledge for understanding its legal arrangements. It will highlight peculiarities of this legal system, taking into account social and political development of international community and pointing out how international rules, created by subjects as States and directed to them, even affect peoples and individuals’ life. The study of essential concepts will be enriched by the examination of cases and materials relevant in international practice and the method used will aim to acquire necessary skills in order to identify and understand principles applicable in the investigation of international legal relations.