Jacek Siewiera is a nonresident senior fellow with the Atlantic Council’s Europe Center, where he focuses on Poland and European security. He is also an associate professor of the Naval Academy and the director for the Baltic Center for Strategic Analysis (Poland).

Siewiera is a former secretary of state and head of Poland’s National Security
Council, where, from 2022 to 2025, he served as national security advisor to the
president during the onset of the war in Ukraine. In this role, he guided work on Polish
national security strategy, defense policy, defense armaments policy, and NATO
cooperation at a pivotal moment for European security.

A retired lieutenant colonel, medical doctor, lawyer, and University of Oxford alumnus, Siewiera combines frontline operational expertise with strategic foresight. He founded the first military underwater medicine clinic. He established the Rescue Center, now the region’s largest civil rescue organization. His leadership in international medical missions—from Lombardy during the COVID-19 outbreak to operations supporting allied forces—earned him recognition from both US and European partners.

Widely regarded as a leading European voice on hybrid threats, dual-use technologies,
and resilience, Siewiera has authored Poland’s first textbook on medical law and holds
multiple EU-protected patents in medical and dual-use innovation.

He is a Clarendon scholar at the Saïd Business School (Oxford) and has also been awarded the Lincoln College Award. His contributions have been recognized with national and international honors, including the Knight’s Cross of the Order of Polonia Restituta (Poland), the Grand Commander’s Cross of the Order for Merits to Lithuania, the Commander’s Cross of the Order of the White Rose of Finland, and the US Military Medal of Merit, State of Illinois.