## 1 Introduction
### Research Methodology  
The methodology of this study consists of three activities: reviewing the existing body of knowledge on diverse BIM guides, identifying POs' opinions on the guides, and suggesting the structure and contents of the STEW guide. Developing a guide inevitably reflects the commonalities among diverse approaches carried out by many professionals, so it is very descriptive rather than analytical. This study is very exploratory in that there has not been such a study before. To address the descriptive and exploratory research characteristics, the authors formulated step-by-step research procedures, as shown in Figure 3.  
As the first step of this research, the authors investigated available domestic and international BIM guides, and analyzed the contents of each guide. Workshops with a Focus Group Interview (FGI) format were conducted twice to meet the research objectives.  
Figure 3: Research methodology.  
The authors used a workshop rather than a questionnaire survey to accommodate the POs' opinions on the existing guides, because the former can elicit more specific and comprehensive critiques from the POs. Eight public agencies from central and local public institutions were invited as the POs to provide their opinions and review the existing guides. Additionally, four experts with profound BIM design experience contributed to the workshops as advisors.  
FGIs are interviews conducted with a group of participants to bring together a variety of information [10]. This is a research technique widely used within the health and social care arena for exploring what individuals believe or feel. FGIs include the use of in-depth group interviews where the participants are chosen as purposive samples of a specific population with similar sociological characteristics. FGIs generate large amounts of data and authentic responses based on the synergy of group discussion and interaction in a relatively short time span, and their findings are used to precede further qualitative procedures. In the process of an FGI, a moderator asks a question to the participants, then takes a step back and allows natural dialogs to arise based on the question. The moderator needs to maintain an environment where the participants feel comfortable and willingly exchange views and ideas about the question [11].  
In the first workshop, the authors performed the role of the moderator in the FGI, and presented the analysis results of the existing guides to the 12 workshop subjects, who defined the desirable BIM guide that could satisfy the research objectives. The subjects then reviewed the analysis results of the existing guides delivered by the authors to figure out whether the guides could meet the desired BIM guide contents. The review results answered yes or no as to the need for a new guide. In the second workshop, based on the results of the first workshop, the subjects were solicited to identify the STEW guide as the structure and advisory contents of the PO-oriented new guide to be developed.  
To enhance the comprehensiveness and practicality of the research, the authors presented their findings to domestic research seminars. The seminars were held four times on a quarterly basis to report and discuss research findings from the Architecture and Urban Development Research Program (AUDRP) funded by the MOLIT for several years; this study was part of that research program. Through the discussion and critique in the seminars, necessary improvements for the STEW guide were identified.