Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Active denial system (ADS), informally called “heat ray”, is a breakthrough non-lethal, directed-energy weapon developed by Raytheon for the US Air Force Research Labs. It is designed for the protection of US military, peacekeeping, crowd control, humanitarian missions, as well as to stop human behavior involved in a riot or other life-threatening situations. Recently, after several years of experimentation for military purposes in Afghanistan and Iraq, the U.S. military leaders have announced the possibility to deploy the active denial system in helping with crowd control. To find out more about ADS, its history and potential effects – read this book.