The combination of the war in Syria and the rise of ISIS has increased the role of non-state actors in the Middle East politics. This is of particular concern for Turkey, on account of its long-standing concerns regarding Kurdish nationalism, particularly after the Syrian war, which provides Kurds with a significant role in regional security affairs. This book aims to examine the regional impacts of the Turkish government's Zero Policy with Neighbors (ZPN) in respect to Iraqi Kurdistan. This has been achieved through an analysis of the impact on the ZPN policy of the following non-state actors between 2011 and 2016: The Syrian Kurdish group represented by the Democratic Union Party (PYD), ISIS, and the Kurdistan Workers party (PKK).