This work is the third Small Wars Journal anthology focusing on radical Sunni Islamic terrorist and insurgent groups. It covers this professional journal's writings for 2015 and complements the earlier Global Radical Islamist Insurgency anthologies that were produced as Vol. I: 2007–2011 (published in 2015) and Vol. II: 2012–2014 (published in 2016). This anthology, which offers roughly five hundred pages of additional analysis, follows the same general conceptual breakdown as the earlier works, and is divided into two major thematic sections—one focusing on jihadi terrorism, insurgency, and the Islamic State in context and the other focusing on US-allied policy and counter-jihadi and counter–Islamic State strategies.