Book excerpt: Avian influenza is a highly contagious viral disease, characterized by intense circulation in the wild waterbird reservoirs, with periodical introductions into the domestic poultry sector. AI viruses have been the source of devastating economic losses in the poultry industry over the last three decades, and have become a major veterinary and public health concern due to their zoonotic potential. The most emblematic illustration of this impact has been the emergence of the HPAI H5N1 virus in southern China in the mid-1990s, followed by its continental spread across East and Southeast Asia, and the unprecedented epidemics recorded in 2003–2004. More recently (from 2014 to 2017), several subtypes of HPAI (including H5N1, H5N6, H5N8) emerged in East Asia and spread intercontinentally, stressing the crucial role of this geographical hotspot as a source of new HPAI subtypes. The international dimension and the difficulty to effectively control those epidemics highlight the need for a global approach to HPAI surveillance and a comprehensive knowledge on epidemiology and patterns of the disease. This Research Topic aims at contributing to fill this gap. It includes ten papers which supplement the knowledge of the epidemiology of AI and offer new approaches on control strategies in various regions of the world.