THE CONCEPTS OF ASYMMETRY and optical activity, although introduced fairly late into inorganic chemistry, have played venerable and central roles in organic chemistry. Modern organic chemistry is usually considered to commence with Friedrich Wohler's synthesis of urea in 1828, and Jean Baptiste Biot's discovery of optical activity in 1812 antedates the very genesis of this field. Moreover, Joseph Achille Le Bel and Jacobus Henricusvan't Hoff's concept of the tetrahedral carbon atom, which constitutes the foundation of stereochemistry, was proposed a century (...) ago (1874), primarily in order to explain the optical isomerism investigated by Louis Pasteur and others. It is to Alfred Werner, the founder of coordination chemistry, however, that we owe the introduction of the concept of optical activity into coordination chemistry, together with its experimental proof. ' The purpose of this paper is to examine and speculate upon the circumstances of Werner's discovery of optically active coordination compounds, to trace its antecedents in earlier work, and to assess its impact upon the future course of inorganic stereochemistry. (shrink)