Benefits and costs of the Czech republic membership in the European union

The aim of the article is a systemic summarization of processes, ways and main determinants influencing the relation between costs and benefits connected with the CR accession to the European Union. Author attempts to find out and to classify moments on macroeconomic both microeconomic level which are relevant for maximization of the realized economic effect. New conditions of the EU single market and importance of quick adaptation of enterprises´ activities to them are being discussed.