Set retarders delay the setting of cement. However, the exact mechanism of how different retarders cause this delay by influencing cement hydration is not fully understood. The two most plausible mechanisms are the adsorption of the retarder molecules onto the surface of the clinker phases, thereby causing an inhibition of the dissolution of the clinker phases , and the admixture-driven stabilization of prenucleation clusters which causes the inhibition of the nucleation of the hydrate phases . In this study, we decouple both mechanisms and investigate the influence of citric acid, tartaric acid, and succinic acid on the dissolution of C 3 S under high dilution, as well as the nucleation and crystal growth of Portlandite and C-S-H.