||There is a wide range of project-management software available, but most of the support it gives is for the planning phase of projects. Existing project-management software generally has insufficient support for many functions: multi-user implementation, group decisions, project tracking, information sources, responsibility tracing and information distribution. On the other hand, workflow technology which is currently emerging is extremely powerful when dealing with some of the weak points of existing project-management software, such as tracking, tracing, and sharing. Therefore, we have designed a project- management system based on workflow technology utilizing existing project-management software functions for planning, coupled to a new system based on workflow technology for the functions of communication, monitoring and control. To provide connection and communication between workflow and project-management software, we propose a common model based on Petri net.