Combining Knowledge Management (KM) with Business Process Reengineering (BPR), this study develops a KM-oriented BPR model. This model integrating KM with BPR can not only be used to strengthen the loosely structured and highly complicated process of the architect/engineering consulting (A/E) firm, but can also increase competitiveness. This study developes and represents business processes based on modified ARIS comprising four points of view, namely knowledge, role, function, and control. This study pioneers the application of single loop and double loop learning methodology within KM to analyze the business operation process. Thus, process performance and service gaps are identified using the Knowledge/Activity/Process Achievement Matrix and Knowledge-Life-Cycle constructing sheets respectively. Based on the process analysis results, a KM-oriented process has been redesigned and developed. Furthermore, the feasibility of the research results is identified and tested by one real case study. To some extent, this study establishes a new agenda of KM-oriented process reengineering for future research.