Pharmaceutical research has a long-standing tradition in Bayer since the estab- lishment of a Pharmaceutical Department 25 years after the foundation of the Farbenfabriken of Friedrich Bayer & Co. in the city of Elberfeld, Germany. In 1888 one of the first antipyretic drugs, phenacetin, was synthesized. A mile- stone was marked by the discovery and launch of Aspirin (TM) in 1899, the most widely used and appreciated drug since then. The success of Bayer 205 (Germanin TM) in the treatment of sleeping sickness 1ed not only to the worldwide recognition of Bayer as a pharmaceutical com- pany but also to intense research into anti-infective therapy. The antimalarial drugs Atebrin TM, Plasmochin (TM) and Resochin (TM) were the first of a whole series of significant contributions and even breakthroughs in the therapy of infections. The advances and the success of antibacterial therapy was heralded by the discovery of the antibacterial activity of the sulfonamides by Domagk, Klarer and Mietsch. The first drug of this class of compounds, Prontosil(TM), opened the new era of therapeutic control of bacterial infections. In 1939 Domagk received the Nobel Prize for Medicine for this breakthrough. A furt her breakthrough in the chemotherapy of the scourge of tuberculosis was achieved in 1946 by Domagk and his colleagues Behnisch, Mietzsch and Schmidt with the development of Conte ben TM, followed shortly afterwards by the discovery of isoniazid (Neoteben TM) by Domagk, Offe and Siefken.