K+S AG (formerly Kali und Salz GmbH ) is an international resources company, headquartered in Kassel, Germany. The company is Europe’s largest supplier of potash for use in fertilizer and, after the acquisition of Morton Salt, the world's largest salt producer. The firm also produces and distributes other mineral fertilizers, such as those from magnesium and sulphur. K+S is mainly active in Europe, North and South America with more than 14,000 employees worldwide (2014).