With the availability of the JT8D turbofan, Douglas started the development of a further Dc 9 stretch. Plans went forward with the Dc 9-60, the Dc 9-55RSS (Re-fanned Super Stretch) and finally the Dc 9-80, formally launched in 1977. The -80 designation was selected in order to reflect upon the planned in-service date of 1980.

From the beginning the aircraft was planned as a family, the baseline Dc 9-81, the Dc 9-82 for improved hot and high performance, and the extended range, higher weight Dc 9-83. All the three versions where re designated the MD 81, MD 82 and MD 83 from June 1983. The 135 seat Dc 9-81 made it's first-flight on October 18, 1979, powered by JT8D-209 engines. Deliveries to Swissair began in September 1980, with other customers for the MD 81 including Aeromexico, Austral Lineas Areas, Austrian, Crossair, JAS, Midwest Express and US Air.

The JT8D-217 powered Dc 9-82 made it's first flight in January 1981, initial deliveres were to Aeromexico, Alaskan, Alitalia, Alitalia Team, ALM, American Airlines, Austrian, Avianca, China Eastern, China Northern, China Northern Swan, Continental, Crossair, Far Eastern Air Transport Corporation, Finnair, Korean Airlines, Meridiana, Midwest Express, Reno Air, Safair, SAS, Spanair, Spirit Airlines and TWA.

The MD 83 took to the air for the first time on December 17 1984, powered by the JT8D-219 engines. It featured additional fuel tanks fore and aft of the centre section. This increased the weight and the floor, wings and undercarriage were strengthened. Deliveries to launch customer Alaska Airlines began in February 1987. Other operators include: Aero Lloyd, Aeromexico, American Airlines, AOM, Austrian, BWIA, Centennial, Crossair, Edelweiss Air, Finnair, SAS, Spanair, Sunway and Transwede.

All three variants had a typical Dc 9-30 fuselage with the fuselage stretched with 8,6m (28ft 6in), and had a small increase in wingspan.

The MD 87 reversed the trend of previous MD 80 series variants, in that it actually had a shortened fuselage. Seating between 107 and 130. The Md 87 incorporated all the structural, technological and avionics improvements of the MD 80 series, but offered a more direct replacement for the original Dc 9 in terms of capacity. The prototype's first flight was in December 4 1986, and entered service with launch customers Austrian Airlines and Finnair during November 1987. The aircraft later entered service with Aeromexico, Great American, Iberia, JAS, Reno Air, SAS, Spirit Airlines and Transwede. The MD 87 was the first member of the MD 80 family to feature an EFIS cockpit, and even a head-up display. The MD 87 was offered with the fore and aft centre section tanks which distingushied the MD 83, and it usually had the JT8D-217C turbofans in stead of the less efficient JT8D-217A engines.

Following the succes of the shortened MD 87, Mc Donnell Douglas launched the MD 83 based MD 88. It combined the airframe and engines of the MD 83 with the EFIS cockpit and new style cabin interior of the MD 87. The MD 88 were delivered to Aerolinas Argentinas, Aeromexico, Air Aruba, Aviaco, Delta, Midwest Express and Onur Air.