Foreword: Swedish Special Operations Command Commander, Brigadier General Anders Löfberg This publication is unprecedented in many ways. It is a unique collaborative, comprehensive, combined, joint effort that addresses an understudied area, namely resistance and resilience. In recent years, most of the contemporary literature and studies have focused on insurgency and counterinsurgency operations concerning the wars and conflicts since 2001. In contrast, this important publication fills a knowledge void (resistance and resilience) in order to complement existing understanding, thoughts, and ideas on insurgencies, conventional warfare, and asymmetric conflict that is apparent today. It is unique because the Resistance Operating Concept (ROC) is an innovative, complementary tool in the modern military arsenal that speaks not only to the military power side of statecraft, but also to the civil society, the broader population, and the civilian defense as a whole. It could be called not just the Joint Force but a “Total Defense Force.” Resistance—resilience together with legitimacy—will undoubtedly evolve into an important component of a nation-state’s defense sovereignty and security in the near future. The underpinning principles are nothing new but will certainly play a vital part in broadening and building the concept of total defense for the time to come. Legitimacy, for example, can be seen as a key factor in how a social unit, structure, or formation is held together and therefore plays a critical role in the cohesion and appeal of a resistance movement, as well as how the conduct of its operations are viewed from the perspective of the all-important population. Resilience and its close companion—perseverance, are vital for a society to overcome adversity and setbacks and generate a unifying fidelity to the mission in the face of arduous circumstances to continue to learn and adapt to achieve its aims.