The S3 was a French land-based Intermediate Range Ballistic Missile, equipped with a single 1.2-megatonne thermonuclear warhead.

In France it is called an SSBS, for Sol-Sol Balistique Stratégique, or Ground-Ground Strategic Ballistic Missile.

[1] From 1971, the main land-based component of the French nuclear deterrent (force de dissuasion) was the S2 missile.

In 1973, a programme was started to develop a second-generation "ground-ground ballistic strategic" (SSBS in French) missile, completed in 1980.

A first 9-missile group was deployed at Apt-Saint-Christol air base, on the Plateau d'Albion in the Vaucluse region, entering service in 1982.