CSAS may refer to:
Canadian Special Air Service Company, an elite post-war parachute unit. Center for the Study of the American South Central Sleep Apnea Syndrome Combined Statistical Area, a statistical unit used by the United States Census and other offices. Coal Smoke Abatement Society, a predecessor to Environmental Protection UK. Community Safety Accreditation Scheme Chattanooga School for the Arts & Sciences Czechoslovak Academy of Sciences Command Stability Augmentation System, a fly-by-wire feature of the Panavia Tornado.