Recently, major inter-city bus carriers in Taiwan have increasingly entered into alliances with other carriers as a means of forming larger networks and improving operation efficiency. However, most of these inter-city bus carriers still use a trial-and-error process to solve their routing/scheduling problems, without optimization from a systemic perspective. Therefore, in this study, we develop a coordinated scheduling model by combining vehicle fleet routing and timetable setting, for the purpose of producing the most satisfactory bus routes and timetables under the alliance. It is expected that the development of the coordinated scheduling model, coupled with the test results, would be useful reference material for practitioners and researchers. To evaluate the proposed model, we perform a case study using real operating data from two Taiwan inter-city bus carriers. The preliminary results are good, showing that the model could be useful for inter-city bus carrier's alliances.