The life and work of Oskars Lucs, a Baltic German stereochemist and the collaborator of the academic Pauls Valdens, is linked with the Riga Polytechnic School (1890–1896), Riga Polytechnic Institute (1896–1910) and the University of Latvia (1919–1939). He investigated the optical activity and the structure of halogen-substituted fatty acids. Together with Gustavs Vanags, he wrote the first manual on organic chemistry in Latvian for higher educational establishements “Organic Chemistry” (1925), and, together with Bruno Jirgensons, he discovered the regularity how to determine the adherence of amino acids either to L or D variety (the law of Lucs-Jirgensons).