This book is an overview of the war in Afghanistan; strategy, military operations and issues for Congress. As the 111th Congress convenes and the Obama administration assumes office, the war in Afghanistan has entered its eighth year. With a deteriorating security situation and no comprehensive political outcome yet in sight, most observers view the war in Afghanistan as open-ended. By early 2009, a growing number of members of Congress, Administration officials, and outside experts had concluded that the effort - often called "America's other war" -- required greater national attention. This book defines "unity of command" and describes how the United States has tried to adhere to this principle since 1914. The evolution of the command structure in Afghanistan since 2001 is also explored. The current command structure in Afghanistan is also analysed. This is an edited, excerpted and augmented edition of a Congressional Research Service and U.S. Government publication.