The U.S. military and intelligence community have shown interest in developing and deploying artificial intelligence (AI) systems to support intelligence analysis, both as an opportunity to leverage new technology and as a solution for an ever-proliferating data glut. However, deploying AI systems in a national security context requires the ability to measure how well those systems will perform in the context of their mission. To address this issue, the authors begin by introducing a taxonomy of the roles that AI systems can play in supporting intelligence-namely, automated analysis, collection support, evaluation support, and information prioritization-and provide qualitative analyses of the drivers of the impact of system performance for each of these categories. The authors then single out information prioritization systems, which direct intelligence analysts' attention to useful information and allow them to pass over information that is not useful to them, for quantitative analysis. Developing a simple mathematical model that captures the consequences of errors on the part of such systems, the authors show that their efficacy depends not just on the properties of the system but also on how the system is used. Through this exercise, the authors show how both the calculated impact of an AI system and the metrics used to predict it can be used to characterize the system's performance in a way that can help decisionmakers understand its actual value to the intelligence mission.