Alfred Werner (December 12, 1866 - November 15, 1919) was a Swiss chemist who was a professor at the University of Zurich. He won the Nobel Prize in Chemistry in 1913 for proposing the octahedral configuration of transition metal complexes.

Werner was born in 1866 in Mulhouse, Alsace. He went to Switzerland to study chemistry at Zurich where he obtained his doctorate in 1890. After postdoctoral study in Paris, he returned to Zurich to teach in 1892, and became a professor as well a Swiss citizen in 1895.
In 1893, Werner was the first to propose correct structures for coordination compounds containing complex ions.
Today Werner's primary valence corresponds to the oxidation state, and the secondary valence is always called coordination number.