The threats posed by domestic groups espousing extremist ideologies, and the cells and lone wolf violent actors they inspire, represent a significant concern to DoD (Winter, 2014). We focus this note on a type of racial/ethnic superiority extremist group that embraces an extreme ideology best characterized as “white supremacy” or the belief that Caucasian people of western European descent are superior to people of all other racial backgrounds because this ideology “will remain the most persistent and lethal threat in the Homeland (DHS, 2020).” Furthermore, this research note focuses on these groups because of their recent rise in global recruitment efforts and, closer to home, their commitment to the overthrow of the U.S. Government (DOS, 2019). In this research note, we summarize data collected on some of the most active and violent groups adhering to or incorporating different elements of white supremacist ideology. We selected these groups because of their activity level within the white supremacy movement, known military ties, capability to engage in nationwide propaganda and recruitment efforts, violent activity, and influence on social media platforms. We detail the following: • National Socialist Movement (NSM), • Atomwaffen Division (AWD)/National Socialist Order (NSO), • Proud Boys, • Boogaloo movement, and • Unaffiliated white supremacists.