Maintaining international security and pursuing American interests is more difficult now than perhaps at any time in history. The security environment that the United States faces is more complex, dynamic, and difficult to predict. At the same time, no domestic consensus exists on the purposes of American power and how best to pursue them. The Center for Strategic and International Studies (CSIS) will look ahead in this annual volume at the crises and opportunities that will likely arise in 2015, how best to deal with them, and what lasting effects they might leave for the next American administration and its allies around the world.