This chapter examines the buildup of an early modern intelligence organization in Sweden during the reign of Gustav Vasa. The prudent king was heavily involved, personally, in all manner of security issues. The greatest perceived foreign security threats against the new dynasty came from Denmark and the German polities. They generated a perpetual sense of danger that stimulated the development of a new type of state vigilance. The king deployed agents throughout Northern Europe and established liaisons with residents abroad. This book shows that royal officials were expected to keep intelligence agents perpetually deployed abroad and demonstrates a proactive rather than reactive approach to strategic security. The sources also provide examples of clandestine intelligence operations where agents operated in disguise. Apart from intelligence operations abroad, emphasis on border security and counterintelligence was also growing. Gustav Vasa had established by the end of his reign a complex but decentralized intelligence organization that provided a firm basis for strategic decision-making. Conclusions suggest that a trait of paranoia was overt in the king’s approach to foreign policy but that it was also highly productive and fuelled the growth of an efficient intelligence organization.