© Springer International Publishing AG, part of Springer Nature 2018. We distinguish several design knowledge types in IS research and examine different modes of utilizing and contributing design knowledge that can take place during design science research (DSR) projects. DSR projects produce project design knowledge, which is project-specific, possibly untested, conjectural, and temporary; thus, distinct from the more stable contributions to the propositional and prescriptive human knowledge bases. We also identify solution design knowledge as distinct from solution design entities in the prescriptive knowledge base. Each of the six modes of utilizing or contributing knowledge (i.e. design theorizing modes) we examine draws on different knowledge types in a different way to inform the production of project design knowledge (including artifact design) in a DSR project or to grow the human knowledge bases in return. Design science researchers can draw on our design theorizing modes and design knowledge perspectives to utilize the different extant knowledge types more consciously and explicitly to inform their build and evaluation activities, and to better identify and explicate their research’s contribution potential to the human knowledge bases.