This article describes the authors' experience of developing a business gaming course for business people in Japan. The course that was developed consists of (a) simple gaming experiments among multiple students using ALEXANDER ISLANDS, a tiny business game on the World Wide Web; (b) lectures to make the students understand the core concepts of business management through the simulation; and (c) a business game developed by the students themselves using business model description language (BMDL), business model development system (BMDS), and automated agent players (AAPs). The course is distinctive in the sense that, through the business gaming, the authors aim to develop students' skills (a) to implement their own models for specific business firms and (b) to understand business processes among companies. This article describes the background and motivation, basic principles, the architecture and implementation of BMDL/BMDS/AAPs, and the experimental results. (Contains 8 figures.)