A lecture given by Claire Davis, at the Adventures in the Physical Metallurgy of Steels (APMS) conference held in Cambridge University. Presents the enticing story about the very rapid processing of steel to produce bainitic microstructures in milliseconds. The ability to non-destructively characterize microstructure is on most steel metallurgists wish list. Electromagnetic (EM) sensors can be used to quantify key microstructural features, not only that but they can be used on-line during steel processing for feedback control. EM sensors can already be used to monitor phase transformation in-situ during cooling after hot rolling, and recent work indicates that they can be used to quantify the phase balance in dual phase steels and therefore predict strength. This may mean that mechanical testing can be avoided, or at least reduced, when producing certain grades of steel, giving large cost and time saving to the steel industry. In the future in-situ systems to measure recrystallisation during annealing, or precipitate formation during tempering may be possible. Indeed there is potential to use different parameters from the complex EM signal response to characterise different steel microstructural features.