The following discussion provides a literature review focused on the hallmarks of pediatric HAE-C1-INH, illustrated by the experience accumulated by the Hungarian HAE Center during the follow-up of 49 children with Type I or Type II HAE-C1-INH (23 males and 26 females with a median age of 6 [4-11] years at diagnosis) from diagnosis to the age of 18 years. The gene discussed is SERPING1; the disease is hereditary angioedema.