The College of International Security Affairs (CISA), formerly known as the School for National Security Executive Education (SNSEE), is one of five colleges at the National Defense University. It is considered the flagship U.S. Department of Defense institution for education in combating terrorism and irregular warfare at the strategic level. According to a Joint Chief of Staff document, the mission of CISA is to "educate joint warfighters and national security leaders in creative and critical thinking for the strategic challenges of winning strategies for the contemporary security environment."