Recently, the importance of service has been emphasized in various industries. However, few studies have
focused on service design in spite of its great relevance. This paper proposes a methodology for service design,
which enables designers to determine existing conflicts in design solutions and obtain basic strategies to solve
them using computers. Two different approaches for detecting conflicts are proposed; one is the use of lexical
expressions of functions, and the other involves the ranges of design parameters. At the end, the verification of
the proposed methodology is carried out through application to an existing case.