Current object-oriented methodologies are inappropriate for development of client-server information system not because they are wrong methods, but because they are too general to apply to every different problem domain and span of development lifecycle. In this paper, we propose a tailored object-oriented methodology that is applicable to system development for specific domain, client-server information system, in practice. The proposed methodology consists of modeling language and development process that reflect characteristics of client-server information system such as business modeling, client-server application partitioning, modeling of collaboration among computing components.