The Global War on Terror brought about several military assistance efforts that include the training and development of foreign security forces. The United States has been providing advisors to foreign security forces around the world for over 120 years. Security force advising maintains a long history within U.S. doctrinal discussions on key components of developing safe and secure environments. Recent changes in military advising doctrine resulted from efforts to make modern military advising more effective. Analysis of multiple cases from the U.S. advisory experience shows that successful advisory efforts share some common approaches. Regardless of the size of the mission, four factors trend toward success when applied in advisory efforts. The advisor needs to account for local political and cultural limitations on the overall effort. The location of the training area needs to provide the ability to minimalize interactions between the host nation's population and the advisors and the elements receiving assistance. The advisory effort needs to include professionalization of other security forces inside a state beyond just the military. Finally, the duration of the mission and the term of individual assignments need to provide the ability to maintain long-term relationships between the advisors and their counterparts.