Early diagnosis and efficient treatment are essential for the rare and incapacitating illness hereditary angioedema (HAE). The global WAO/EAACI guideline on diagnosing and managing HAE has been revised and updated and now offers the most recent management advice. An international panel of experts examined the available data for the update and revision of the guideline, came up with 28 recommendations, and reached a consensus via the DELPHI method. By offering advice on common and significant clinical issues, such as how HAE  should be diagnosed, the recommendations aim to assist physicians and their patients in making rational decisions in the management of HAE with short C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2). What therapies should be used, when patients with HAE should receive preventive, in addition to on-demand, treatment, treatment objectives, if treatment of HAE in specific patient populations (children or nursing mothers) should differ, and how patients with HAE should track their condition’s progression, effects, and management are all addressed. The guideline also aims to encourage and facilitate the use of suggested diagnostics and treatments for all patients and contribute to developing international standards for the management of HAE.