Respiratory therapists assist physicians in the diagnosis, treatment and care of patients with respiratory and cardiopulmonary disorders. Clinical perfusionists provide technical support to patients undergoing cardiac surgery and patients requiring cardio-respiratory support. Cardiopulmonary technologists assist physicians in the technical aspects of diagnosis and treatment of cardiovascular and pulmonary disease. Respiratory therapists are employed in hospitals, extended care facilities, public health centres and respiratory home care companies. Clinical perfusionists and cardiopulmonary technologists are primarily employed in hospitals. Respiratory therapists, clinical perfusionists and cardiopulmonary technologists who are supervisors or instructors are included in this unit group.