Due to the significant increase of theoretical evaluation of software prototypes, design science research (DSR) as a new research direction has emerged in recent years with the aim to ensure for both, rigor and relevance in prototyping research projects. On the one hand, a theoretical background ensures a usable and professional software prototype and on the other hand, new and innovative software prototypes provide rich data for theory testing and evaluating. DSR has proven to produce practically relevant research results but unfortunately it is still not a fully accepted research approach since it has somehow failed to develop theoretical contributions. Nevertheless, we believe that design science research is an important key factor for a new and innovative research paradigm. This paper provides an overview of DSR and tries to combine both, rigor and relevance, in a unified perception.