in English The object of this diploma thesis is to answer the question, how can international organizations (UN, Council of Europe and OSCE) effectively regulate conflicts among their member states, or which instruments are they for this purpose equipped with. The thesis is divided into three main parts - theoretical study, part dedicated to the individual international organizations and the case study. The first part offers a definition of basic legal concepts, as they will be used in the following parts of the study with an emphasis on the definition of the concept "coercion". The following part deals with the instruments of coercion the international organizations are equipped with. In the third part are the findings from the previous parts confronted with a real case of the effort to regulate the conflict between Azerbaijan and Armenia in Nagorno Karabakh. This structure of the thesis can be also described as a progress from a theoretic basis, through an applied theory contained in particular agreements, to their practical realization in the concrete case. Based on the completed study the author concludes that unilateral instruments of coercion, that the particular organizations have at their disposal, are often not appropriate (exclusion from organization), ineffective (political declaration)...