Phil Gurski's
Western Foreign Fighters: The Threat to Homeland and International Security (Rowman and Littlefield, 2016) is his second recent monograph on terrorism, and another useful resource for practitioners and non-specialists alike. Written in an approachable, grounded style,
Western Foreign Fighters is both topical and novel; its comparative analysis of volunteers' participation in non-sanctioned conflicts both jihadist and secular is especially notable. Gurski's measured, thoughtful analysis is a credit to the Canadian intelligence community (wherein he spent his entire career) and I look forward to his further publications.