Our research addresses the problem of managing and coordinating information resources used in information system (IS) development. In our approach, we argue that conceptual specifications of information systems are the fundamental constituents of information resources. Accordingly, the first challenge of the research is to manage and coordinate conceptual specifications used in IS development. For this reason, an "Information System upon Information Systems" (ISIS) is proposed to manage and coordinate information resources based on conceptual specifications of information systems. An ISIS is actually a typical information system, which supports other information systems in development. Correspondingly, this thesis presents a conceptual framework for building and managing the ISIS. This conceptual framework describes how to identify, modularize, manage, represent, and coordinate conceptual specifications used in IS development. In conclusion, the thesis ends with the current results, present works and remaining research issues.