Sigma -Aldrich is one of the largest producers and distributors of research chemicals worldwide. The Group's headquarters are located in St. Louis, United States. The five combined company Sigma ( not to be confused with the Japanese manufacturer of lenses, digital cameras and flash units ), Aldrich, Fluka, Supelco SAFC and together form the SIGMA -ALDRICH Corporation. The Company's shares are traded on the NASDAQ and are included in the NASDAQ -100 Index as SIAL.

The company has branches in Germany in Hamburg, Quick village, Seelze, Steinheim and Taufkirchen ( near Munich ) and in Vienna in Austria.

The management was until 1991. In the hands of the Vienna-born chemist Alfred Bader, the Aldrich also founded in 1951 and now works with his wife as an art collector and patron