The research agenda of the most influential Polish think tanks involved in providing informational and expert support for foreign policy activities has been examined. Key political and economic aspects of the implementation of the “Three Seas Initiative,” which are the focus of attention of the Polish expert community, have been identified. Based on the body of publicly available expert opinions and analytical reports, the article presents an assessment of the activities of these think tanks, which substantively contribute to shaping the zone of Poland’s primary foreign policy and foreign economic interests within the framework of the “Three Seas Initiative”.