This work explores the history of U.S. Army deception and doctrine, and combines the insights gained with the various works on deception, cognitive psychology, communications, and decision-making in order to distill a concise handbook for deception practitioners. A longitudinal review of U.S. Army doctrine reveals a wide variation in the treatment of deception, from emphasized to ignored. This variation can be primarily explained by the U.S. preference for the cumulative destruction style of war and the perceived balance of power between the U.S. and its adversaries. This work strives to fill the current doctrinal gap by distilling the existing body of work to create a theory of deception in the military context. The theory presented provides a cogent structure, taxonomy, and lexicon; as well as, emphasis on how deception functions within the frameworks of communications and decision-making. Next, a synthesis of the practice of deception is presented, with a focus on deception planning and the essential elements of deception practice. Examples of U.S. use of deception from the Revolutionary War to Operation DESERT STORM are presented to provide illumination on the utility and use of deception. Finally, the work provides recommendations on how to organize for deception operations.