In this paper, we propose to consider the ActivityBased Costing (ABC) method as a design science artifact. We apply the three cycles of design science (i.e., relevance cycle, rigor cycle, and design cycle) to Activity-Based Costing. We argue that some cycles are addressed in literature to a certain extent, but that justificatory knowledge in the rigor cycle is missing. Applying such knowledge can provide valuable insights for systematically evaluating and improving an artifact. Therefore, we propose modularity and entropy as possible candidates for such justificatory knowledge. This paper contributes to ABC research by introducing a scientifically rigorous evaluation. This evaluation indicates several possibilities for design contributions to ABC. Moreover, the relevance of these new artifacts for cost accounting practice are discussed as well.