Social media is playing an important and increasing role in U.S. military information operations (IO), because people around world, including civilian populations, U.S. allies, and U.S. adversaries, use social media platforms to share information and persuade others. The rapid growth of the communication technologies that underpin social media platforms has given non state adversaries an asymmetric advantage, as have the low cost of entry and the relative operational agility with which they, in contrast to established bureaucracies, can access and utilize new technologies. And so, while there are compelling national security reasons to field a social media analysis capability, the U.S. Department of Defense (DoD) must do so both while navigating U.S. law and cultural norms and under conditions of great uncertainty. Amid quickly evolving technologies and communication trends, there is a risk that DoD could invest in soon-to-be obsolete capabilities or encounter other challenges in building its analytic capacity and applying it in an effective and practical manner. This report explores these complex issues and offers DoD a set of recommendations for building a social media analysis capability in support of IO that ably and appropriately enhances national security. It should be of particular interest to the U.S. military joint information operations community. Given both the urgency and the challenges in developing this capacity, and in light of a congressionally mandated assessment, DoD has a clear need for a research survey of the existing literature on social media analysis technologies, best practices, legal and ethical constraints to social media analysis, and the intersection of IO and social media analytics.