α1-Antitrypsin deficiency (AATD) is an autosomal-codominant genetic disorder that predisposes individuals to the development of liver and lung disease. AATD is greatly underrecognized and underdiagnosed. Early identification allows preventive measures to be taken, the most important of which is the avoidance of smoking (including the inhalation of second-hand smoke) and exposure to environmental pollutants. Early detection also allows careful lung function monitoring and augmentation therapy while the patient still has preserved lung function. Cost factors and controversies have discouraged the initiation of large-scale screening programs of the newborn and adult populations in the United States and Europe (except for Sweden). There are sound medical reasons for targeted screening. Evidence-based recommendations for testing have been published by the American Thoracic Society/European Respiratory Society task force, which take potential social, psychological, and ethical adverse factors into consideration. This review discusses rationales for testing and screening for AATD in asymptomatic individuals, family members, and the general population, weighing benefits against potential psychological, social, and ethical implications of testing. For most, negative issues are outweighed by the benefits of testing. AATD testing should be routine in the management of adults with emphysema, COPD, and asthma with incompletely reversible airflow obstruction.