This book is the first collection of scholarship featuring both Canadian and American scholarship on the resurgent right-wing extremist movement in the two countries. It is particularly timely given the recent rise in political populism that has engendered renewed activism from extreme right contingents. Trump's right-wing populist and white nationalist political campaign has galvanized Canadian and American white supremacist ideologies, identities, movements and practices. Leading Canadian and American scholars are brought together to explore a contemporary array of current dynamics, patterns and characteristics associated with the movement in each country. Split into four sections, it provides an introduction to extremism in the 21st century, it examines studying extremism, forms of extremist activity and violence, and the responses. The collection allows comparisons to be drawn out from the distinct treatments of each country. It speaks to students as well as scholars in social sciences departments, including criminology, sociology, social justice, and terrorism, peace and security studies, and political-violence related programs.