In both service industry and manufacturing industry, customer participation in the design and formulation is promoted as a way to add value. Providers, who are experts of their services and products, construct the relationship between domain on customer requirements and that on function of services and products, with their knowledge. Based on the relationship, providers try to design service and products fit for customer requirement. In case customers participating on the design, though customers have less knowledge about services and products than experts, they have to decide how they design service and products like experts. This study defines customer expectation as what acts as a substitute for the knowledge in customers' design and aims to clarify customer expectation in order to encourage participatory design. As an example, this study examines customer expectation on the tourism service in Tokyo. Questionnaire asks tourists about what tourists regard as important when they plan their tourism. From the questionnaire data, customer expectation is analyzed. The difference between the result of analysis to Japanese subjects and that to foreign subjects suggests that the relationship between the domains depends on customers' knowledge and experiences.