This paper reviews current research that aims to understand and manipulate the properties of advanced steels through control of the nanostructure, with an emphasis on thermomechanically produced steels. While the concepts of such strengthening mechanisms have been understood and used for many years, it is now possible through advanced characterisation methods to gain detailed insights. Similarly, our knowledge of phase transformations supported by improved modelling also allows us to design microstructures that have length scales in the range of 10–100 s of nanometres. Examples are provided that relate to the application of this concept in Advanced High Strength Steels of precipitation hardening, bake hardening, the development of ultrafine ferrite microstructures, nanoscale dispersed multiphase steels and nanoscale bainite.