a grease composition which has a good compatibility with boots made of rubber or thermoplastic elastomer , and which also gives enhanced endurance , low wear and low friction in use in constant velocity joints is disclosed . a grease composition is suggested comprising a ) at least one base oil ; b ) 5 % by weight to 40 % by weight of at least one calcium sulphonate soap and / or calcium sulphonate complex soap as a thickener ; and c ) at least one molybdenum containing additive .