High-speed lubricating greases easily cope with speeds which can normally only be achieved through the use of lubricating oils. Their consistency corresponds to that of usual rolling bearing greases (e.g. NLGI grades 1 or 2). For speed factors below 1 million [mm ∙ min−1], high-speed roll- ing bearing greases have provided excellent operational performance for a great many years. More recently, new extreme-speed greases have been developed enabling operational speed factors in excess of 2 million [mm ∙ min−1]. These greases fulfil lifetime lubrication conditions in, e.g. machine tool spindles enabling lowest operating temperatures.