North Korea is a closely controlled society, and its regime has taken actions that threaten the United States and other United Nations member states. North Korean tests of nuclear weapons and ballistic missiles have prompted the United States and the UN to impose sanctions on North Korea. This book identifies the activities that are targeted by U.S. and UN sanctions specific to North Korea; describes how the United States implements its sanctions specific to North Korea and examines the challenges it faces in doing so; and describes how the UN implements its sanctions specific to North Korea and examines the challenges it faces in doing so.