Design of the Gulfstream III started with an effort to synthesize a completely new wing employing NASA supercritical airfoil sections and winglets.

The fuselage is 2 ft (0.6 m) longer aft of the main door, the radome is extended and there is a new curved windshield.

The aircraft received its type certificate from the American Federal Aviation Administration on 22 September 1980.

[5] In 2013, the FAA modified 14 CFR part 91 rules to prohibit the operation of jets weighing 75,000 pounds or less that are not stage 3 noise compliant after December 31, 2015.

[15] N30LX (cn 438) has been modified by the addition of a ventral canoe and sensor turret as the "Dragon Star" Airborne Multi-Intelligence Laboratory for use by Lockheed Martin.

Modifications include a centerline pylon[18] and a dorsal satcom radome[19] Two Gulfstream IIIs, K2961 (cn 494) and K2962 (cn 495), equipped with long-range oblique photography cameras mounted in the fuselage, were delivered to the Indian Air Force.