The dramatic rise and spread of emerging threats posed by state and non-state actors as well as new forms of insecurity altered significantly the agenda of global and regional security. This introductory chapter to an edited book first briefly reviews the basic characteristics of these new forms of challenges or non-traditional threats, which are qualitatively different from the conventional threats characterizing the international security environment. Then, the chapter also briefly notes how those threats are tackled in the security policies within NATO and GCC contexts. After providing analytical summaries of the individual contributions forming the edited volume, the chapter moves to offer a comparative analysis and identifies several cross-cutting issues raised by the contributors. Among others, the chapter identifies following themes: the dual role of technology as a threat multiplier and capability enabler, the blurring of lines between threat categories, the indivisibility of security and trans-regional security dynamics, institutional and conceptual adaptation challenges, and policy relevant recommendations for enhancing NATO-Gulf cooperation.