Respiratory therapists, also known as respiratory care practitioners, evaluate, treat, and care for patients with deficiencies or abnormalities of the cardiopulmonary (heart/lung) system by either providing temporary relief from chronic ailments or administering emergency care where life is threatened. They are involved with the supervision of other respiratory care workers in their area of treatment. Respiratory technicians have many of the same responsibilities as therapists; however, technicians do not supervise other respiratory care workers.

Working under a physician's direction, these workers set up and operate respirators, mechanical ventilators, and other devices. They monitor the functioning of the equipment and the patients' response to the therapy and maintain the patient's charts. They also assist patients with breathing exercises, and inspect, test, and order repairs for respiratory therapy equipment. They may demonstrate procedures to trainees and other health care personnel. Approximately 122,400 respiratory therapy workers are employed in the United States.