This document summarizes an article about deterring information warfare. It defines information warfare as actions taken to preserve one's own information systems while exploiting an adversary's systems. It describes several types of information warfare, including attacks on command and control, electronic warfare, and cyberwarfare. It identifies the primary threat as an adversary's ability to alter, replace, or delete information in systems or influence information processes. Advanced information technologies are required to disrupt systems through information warfare, representing a threat to all nations. Confidence building measures from the nuclear era, like deterrence and non-proliferation, may provide initial concepts for addressing this new threat.