Readers will embark on a journey through the immune system, gaining insights into the roles of mast cells, basophils, and the complement system in the development of angioedema. An exploration of vascular anatomy and cellular mechanisms provides a foundation for understanding the pathophysiology of this condition. The treatise navigates through hereditary and acquired forms of angioedema, uncovering the genetic and immunologic underpinnings, clinical manifestations, and triggers.