Candidate materials for the hardened steel raceways in ceramic-ball hybrid bearings, as well as steel components for other advanced bearing designs, are being increasingly specified to be capable of attaining combinations of material properties that have not previously been required of traditional bearing steels such as 52100, M50, and 440C. The desired properties may include one or more of the following: greater attainable hardness for higher static load capacity, good hot hardness and material stability at elevated operating temperatures, better adhesive and abrasive wear resistance to minimize galling or raceway damage under contaminated running conditions, good corrosion resistance for bearings which may be exposed to corrosive operating or storage environments, adequate shock loading survivability for potential satellite launching, and good fatigue life characteristics. A number of recent bearing industry publications have discussed some of the properties and laboratory bearing test results for CPM VIM CRU 20, which is a cobalt-free high-carbide-volume PM high speed steel with 66 HRC min. attainable hardness and good hot hardness characteristics. Although this material remains one of the leading candidates for the hardened steel raceways in several of the hybrid bearing designs developed to date, it has low chromium content and therefore inadequate corrosion resistance for the operating conditions or storage environments anticipated for other bearing applications. The potential application of more recently developed high-chromium and high-vanadium PM tool steels for advanced bearing designs with unique combination of corrosion resistance, high attainable hardness, and exceptional wear resistance is discussed.