Sigma-Aldrich is a leading Life Science and High Technology company. Our roots go back to the early 1950s when Sigma and Aldrich independently developed as suppliers of biochemicals and organic chemicals, respectively. Sigma and Aldrich merged in 1975. Since then, the Sigma-Aldrich group has grown to include: Fluka Chemie GmbH - headquarters in Buchs, Switzerland, Ridel-de Haen - headquarters in Seelze, Germany, Supelco - headquarters in Bellefonte, Pennsylvania, USA. Today, we refer to these units as brands within Sigma-Aldrich. Each has specialties as described in the Compound Descriptions associated with the brand names.