Within the recent history, the world has experienced dramatic events which had a substantial effect on the “struggle” between data protection and security measures. This “struggle” can be clearly seen in the issues of data transfer from the European Union to the United States of America - the “struggle” between the US demands for access to information and the EU data protection compliance obligations. How much of European air passenger personal data should be shared with the US authorities and under which conditions should this take place? The thesis examines the problem, its background, the key terms and legal instruments. It discusses and analyses the development of “solution” of the problem (a serie of EU-US agreements, ending up with current agreement of 2007), development of the situation afterwards, as well as further steps and proposals, inter alia, the proposed EU system aimed in stronger security measures enforcement. The work concludes by pointing out the unlawfulness of former and current data transfers and sets forth the author''s perspective on how the overarching problem can be resolved.