[en] Steel is a particularly challenging material to semi-solid process because of the high temperatures involved and the potential for surface oxidation. Here, the experience of semi-solid processing is reviewed and the current situation in relation to commercial application is assessed. The review will include discussion of the range of potential steel materials which are amenable to thixoforming and identification of suitable steels; modeling of die fill and rheological properties of semi solid steel; technology considerations for industrialisation; die development and the properties of thixoformed products.