The American Thoracic Society (ATS) is a nonprofit organization focused on improving care for pulmonary diseases, critical illnesses and sleep-related breathing disorders.

[1] More than 15,000 physicians, research scientists, and nurses and other allied healthcare professionals (32 percent of whom work outside the United States).

[3] With the overarching goal of advancing the Society's mission, each chapter represents a state or other geographical area and includes, in its membership ATS members.

4 peer-reviewed journals: The Society offers Continuing medical education credits and nursing contact hours through its annual international conference.

The Society is actively involved securing funds for basic and clinical research, establishing global tuberculosis and tobacco control policies, enforcing the Clean Air Act, and lobbying for fair reimbursement for physician services under Medicare and other insurers.