This publication is the keystone document for communications system support to joint operations and provides guidelines to our commanders regarding information systems and networks as a part of the Global Information Grid. A vast array of information, underpinned by joint doctrine, is utilized to employ combat power across the broad range of military operations. The communications system provides the means to synchronize joint forces. Improved synchronization among joint and multinational forces and with non-Department of Defense agencies, with greater reliability and enhanced security - achieved through sound employment of information technology - is essential for effective command and control in the network enabled environment of the 21st century. Information systems and networks provide the predominant source from which the warfighter generates, receives, shares, and utilizes information. The synthesis of advanced communications system capabilities and sound doctrine leads to information superiority, which is essential to success in all military operations.