Operations Enduring Freedom and Iraqi Freedom were the first major wars of the 21st century. They will not be the last. They have significantly impacted how the U.S. Government and military think about prosecuting wars. They will have a generational impact on the U.S. military, as its future leaders, particularly those in the ground forces, will for decades be men and women who served in Iraq and Afghanistan. It is imperative that leaders at all levels, both military and civilian, share their experiences to ensure that we, as a military and as a country, gain appropriate insights for the future. When General George W. Casey, Jr., was the Army chief of staff, he encouraged leaders at the war colleges, staff colleges, and advanced courses to write about what they did in Iraq and Afghanistan so that others could be better prepared when they faced similar challenges. This book is General Casey’s effort to follow his own advice, offering narratives and insights about his tenure as commander of Multi-National Force–Iraq so that future leaders can be better prepared for the next conflict.