Measuring the effectiveness of deterrence activities and messages is challenging since the adversary will not admit to being deterred. This study proposes that planners can use intelligence indicators to provide feedback for measuring deterrence effectiveness. Reviewing the evolution of U.S. deterrence strategy, as well as, current U.S. deterrence strategy provides planners with the desired end states and principles for executing deterrence operations. A search for joint deterrence doctrine disclosed that such doctrine does not exist In the absence of deterrence doctrine, this paper reviewed four historical cases. These cases demonstrate that a multitude of indicators showed deterrence activity effects, yet the U.S. did not always adjust its deterrence strategy to successfully influence the adversary. A review of military deception doctrine and historical deception operations provides guidance for successfully influencing adversary decision makers. Using the military deception operations lessons learned combined with four historical case observations, this study proposes an indicator list that planners can use to develop priority intelligence requirements to measure deterrence effects.