In burn surgery the quick and correct assessment of the burn depth is critical to improve healing and reduce scarring of thermally injured skin. Still, it is challenging to work out where skin grafting is needed and even experienced surgeons fail. In the recent years, millimeter wave imaging systems have proven to be of great potential in severe burn injury diagnostics. In this talk an analytical model of the relative permittivity of the skin, simulation results and ex-vivo as well as in-vivo measurement results of a radar tomography and nearfield imaging technology are presented and discussed to illustrate their potential for the assessment of burn injuries.