Researchers in the area of Information Systems (IS) applying the design science paradigm are confronted with the challenge to make theoretical contributions which also help to solve current and anticipated problems in practice. This is often referred to as the rigor and relevance challenge of design science research. To ensure relevance of the research outcome, research projects in IS are often conducted in close cooperation with one or more industry partners. This typically leads to a need for early results and a binding to the specific organizational context of the participating industry partner(s). In this paper, we propose pattern-based design research (PDR), an iterative design research method consisting of four phases, to overcome this problem. We argue that patterns as early stage design artifacts enable researchers to build innovative artifacts that address current and anticipated problems of practitioners in an organizational context. Building on well-established concepts as patterns, design theories, and the design theory nexus, the proposed research method enables a researcher to theorize and learn from the intervention at the industry partner(s) while performing rigorous and relevant design science research. We illustrate the applicability of PDR by presenting a research project from the area of enterprise architecture management.