Abstract: Mobile business, that is, conducting business activities as well as delivering content and services over the wireless Internet, is regarded as one of the key emerging areas in electronic business. Whereas adoption and usage of mobile business in several markets has remained far behind initial expectations, the case of NTT DoCoMo’s i-mode in Japan is a famous example for success in mobile business, with many players at different steps in the mobile value chain thriving at the same time. In our analysis, we assume a perspective different from the existing approaches for explaining i-mode’s success. Analyzing the economics of the i-mode system, we argue that NTT DoCoMo has been able to install its business model and secure its own position by employing a novel strategic management concept, which we term “value scope management.”