Because of the seamlessly international nature of the Internet, effective cyber security demands close cooperation with allies and friends overseas. Yet, because of the relatively young status of the discipline, national approaches to organizing and providing for cyber defense vary widely even among those countries whose interests are most closely aligned with those of the United States. The result is that the bodies and structures responsible for cyber defense, and their affiliations and mandates, can be difficult to understand. In this Letort Paper, British cyber policy researcher Keir Giles and German computer security specialist Kim Hartmann provide an overview of four different national approaches to cyber defense: those of Norway, Estonia, Germany, and Sweden. While providing a useful guide for engagement with the relevant governmental and other organizations in each of these countries, the Paper also compares and contrasts the advantages and drawbacks of each national approach.