The Société Alsacienne de Constructions Mécaniques, or SACM, is an engineering company with its headquarters in Mulhouse, Alsace, which produced railway locomotives, textile and printing machinery, diesel engines, boilers, lifting equipment, firearms and mining equipment. SACM also produced the first atomic reactor at Marcoule.

Mulhouse is a city of the European Collectivity of Alsace, close to the Swiss and German borders. It is the largest city in Haut-Rhin and second largest in Alsace after Strasbourg.