Limestone Calcined Clay Cements (LC 3) permit to continue decreasing the clinker factor in cement. Two widely-available Supplementary Cementitious Materials (SCMs) are used in LC 3 : calcined kaolinitic clays and limestone. The combination of these two SCMs allows additional reactions compared with conventional cements, leading to a high space-filling and excellent properties. Clays with only 40% of kaolinite can be used in LC 3 , providing sufficient strength, higher resistance to chloride ingress and alkali-silica reaction.