Robustness is the ability of a concrete mixture to satisfy its defined requirement profile despite any unfavorable influences, they may be predictable or unpredictable. The objective of this study is to investigate ways to increase the robustness of SCC by means of specific mixture proportioning, especially in the fine grain and powder range. The Superplasticizer Based Approach and the characteristic boundary consistency curves are tools whereby the general robustness of grain compositions can be estimated. Furthermore the Superplasticizer based Water Demand is proven to be a useful tool to characterize grain compositions concerning their packing density, which in turn is an important information to ensure the necessary surplus of fines in the overall mixture proportioning. By several examples it is demonstrated how little changes in the powder composition can cause major changes in concrete properties and how such influences can be determined effectively.