The introduction of the Chevrolet Citation marked the drastic downsizing of GM's 2nd generation X-platform, almost reducing its exterior footprint to dimensions of the '71–'80 H-platform (sub)compacts. While the Citation replaced the long-running Chevrolet Nova, it shared the X-platform with the Pontiac Phoenix – sharing the hatchback bodies of the Citation – as well as the Buick Skylark and Oldsmobile Omega, which were given their own sedan bodywork. The Citation notchback coupé body was unique to Chevrolet.