The present work describes a novel 2.4 wt. % carbon high-vanadium powder metallurgy (PM) steel that was transformed into bainite and tempered martensite, resulting in structures with very high hardness. The alloy design and the underlying heat treatment concepts are presented with the aim of tailoring the structure to suit very demanding rolling bearing applications such as in aeroengine bearings and auto sports. In the as-hardened condition, the observed very high hardness somewhat contrasts with the modest alloying of the steel alloy, as well as the not so high austenitization temperatures that were used. Consequently, an attempt was made to characterize the structures using transmission electron microscopy in order to identify a possible mechanism, or explanation, for the observed high hardness. On the basis of the results obtained so far, future work is proposed.