John Julian Hamre is an American international relations scholar and former senior defense official. He is the president and CEO of the Center for Strategic and International Studies, a position he has held with since 2000.

The Center for Strategic and International Studies (CSIS) is an American think tank based in Washington, D.C. From its founding in 1962 until 1987, it was an affiliate of Georgetown University, initially named the Center for Strategic and International Studies of Georgetown University. The center conducts policy studies and strategic analyses of political, economic and security issues throughout the world, with a focus on issues concerning international relations, trade, technology, finance, energy and geostrategy.