During the last 25 years, developments and innovations in flat steel production (hot strip, plate and cold strip) have been characterized by growing demands on the quality of the products and increasing cost pressure. This has triggered numerous innovations in plant engineering as well as control and regulation technology solutions aiming at optimizing product quality, enhancing productivity and reducing energy consumption. Many of these efforts have been focused on the integration of systems measuring and controlling different parameters, such as temperature, profile, flatness, surface, roughness and coating thickness. Growing process computer capacities and the advancing use of computers in production have helped to improve product quality and increase production.