This monograph provides a complete and up-to-date description of the AATD. It covers basic biology, genetics, laboratory diagnosis and the main organic manifestations; describes the clinical presentation of the AATD in adults and children; and features chapters on genetic counseling, patient opinions, and future therapies. The content has been designed to meet the needs of the physician, who cares for patients with lung and liver in daily practice, and the general practitioner, who is responsible for the medical guidance of these patients. The monograph has the participation of Ph. Miravitlles, Coordinator of the Catalan Center of Excellence for Alpha-1 Antitrypsin Deficit.