Karl Landsteiner is best known for his discovery of the human blood goups. The revolutionary discoveries of this brilliant scientist in other fields have not received the recognition they deserve. His demonstration that poliomyelitis is transmissable showed the way of modern virology. His studies opening the field for epitope recognition, which he himself considered his main achievement, laid the foundation for research ongoing in our days. This book with its outstanding contributors is but a small tribute to this visionary scientist.