This article attempts to consolidate theorizing about the radicalization of Western homegrown jihadists. Five major models of radicalization are reviewed. The commonalities and discrepancies among these models are identified and analyzed in the context of empirical evidence in the field of terrorism research and social psychology. Three psychological factors emerge as contributors to radicalization: group relative deprivation, identity conflicts, and personality characteristics. Avenues for future research concerning the radicalization of homegrown jihadists are suggested, focusing on research that may not only be practical for counter-terrorism, but also feasible given the challenges of research with radicalized individuals.