This report examines the various analytic tools that have been developed to understand the causes and dynamics of radicalization and violent extremism. The report assesses the strengths and limitations of these tools in informing the design of P/CVE interventions. It considers micro- and macro-level frameworks and models, and the various contexts in which they may be relevant. A companion report, “Measuring Up: Monitoring and Evaluating P/CVE Programs,” examines tools for assessing the impact of such programs.