This book examines the international forums in which states develop cyber norms—“rules of the road” for how governments use information and communication technologies. To understand the dynamics in this emerging field of diplomacy, the book focuses on an often-overlooked actor: Brazil. With the international debate dominated by two camps that can be broadly characterized as the West versus China and Russia, the book demonstrates that Brazil holds a key position as a bridge-builder between these two sides. It paints a rich picture of Brazil’s efforts in shaping cyber norms across such diverse forums as the United Nations, BRICS, and the Organization of American States, while contextualizing these activities in Brazilian domestic cybersecurity policy and foreign policy traditions. This rich case study paves the way for a deeper understanding of how different actors shape international cybersecurity policy.