The use of alkali-activated binder systems is becoming increasingly important in concrete technology. Beside ecological questions, especially the reduction of CO2 emissions when producing these binders, there is continually increasing interest in the fact that particular concrete properties can be improved by using these binder systems. Alkali-activated binders with lower calcium contents are also called “geopolymers”. The reactions of a geopolymer binder system required for strength formation differ significantly from those reactions already known from systems based on Ordinary Portland Cement (OPC). In OPC-based systems it is calcium silicate hydrate phases that are predominantly formed, whereas in the case of geopolymer systems, inorganic three-dimensional aluminosilicate networks will occur. In this paper, the results of extensive laboratory tests as well as several practical applications of a geopolymer concrete with a binder system consisting of a ground granulated blast furnace slag, fly ash, and custom made chemical activators are presented with respect to special properties of such systems, e.g. high resistance to chemical attack.