In the aftermath of the information sharing failures leading to the September 11, 2001 terrorist attacks that killed nearly 3, 000 people in New York City, at the Pentagon, and in a Pennsylvania field, states and localities across the United States established what are known today as State and Major Urban Area Fusion Centers. Collectively known as the National Network of Fusion Centers, many of these (now numbering 78) fusion centers are still in their infancy. The Homeland has been attacked five times since 2001: the Little Rock Recruiting Station shooting (2009); the Fort Hood shooting (2009); the attempted bombing of Northwest Airlines Flight 253 on Christmas Day (2009); the attempted car bombing in Times Square (2010), and the Boston Marathon bombings (2013). In the wake of these attacks, we have come to understand that homeland security, including counterterrorism efforts, must be a national responsibility, a true and equal partnership across all levels of government, and inclusive of the American people themselves. A top down, wholly federal approach simply does not and cannot suffice. Fully integrating state and local law enforcement and emergency response providers as national mission partners requires a grassroots intelligence and analytic capability. This book provides a comprehensive study of the National Network of Fusion Centers in an effort to understand current strengths and gaps and provide recommendations for improvement.