For over 30 years, the U.S. Nuclear Regulatory Commission (NRC) has maintained effective nuclear security, emergency preparedness and incident response programs. The NRC requires safe and secure operations at nuclear facilities wherein safety refers to operating the facility in a manner that protects the public and the environment. Security refers to protecting the facility from adversaries who wish to harm people and the environment. Safety and security are accomplished by using people, equipment and physical protection. This book explores the safety and security threats to our nation's nuclear facilities and the measures and techniques in place to thwart any such emergency.