The rolling-four-ball test, which closely simulates the rolling and sliding experienced in angular contact ball-bearings, has been used to study the influence of the steelmaking process on the rolling contact fatigue properties of steels used for rolling bearings. Commercially available balls, as well as specimens made from conventional En-31 and various special high-speed tool-steels manufactured by different processes, have been compared. Methods of improving steel quality, such as vacuum induction melting, vacuum consumable arc melting and vacuum degassing have been assessed. The same types of steel manufactured by similar methods by different steelmakers have been tested. Significant differences in performance have been found between different types of steel and between the same types of steel manufactured by different processes. Acid material was generally superior to basic material, and vacuum techniques were beneficial. Modifications in the steelmaking procedure which improved material properties gave increased resistance to rolling contact fatigue. The effect of the steelmaking process was found to be similar with all steelmakers. Observations of significance in the study of the mechanism of failure have been made.