The Success or Failure of the Requirements Definition and Study of the Causation of the Quantity of Trust Existence Between Stakeholders

Requirements definition that is an important work process for a project and may determine the success or failure of system development project tends to draw an ambiguous conclusion, which will lead directly to the failure of such a system construction. To optimize the requirements definition process we present a model that the trust management process is integrated into the requirements definition process, as measures to minimize the gap between requirements caused due to a lack or discrepancy in communication that is produced easily in requirements definition and to use a negotiation method for solving problems in the following processes provided by the gap between requirements including tacit ones. We discuss a matter that building trust between the stakeholders in the requirements definition process is effective to optimize the requirements definition, which has been produced by the special characteristics of Japanese firms in the information system development, and we also describe the necessity and effectiveness of information system in Japan.