Abstract
Each project requires capacity of different resources at different time period, and each enterprise has different available capacity of resources at different time period. As a result, an enterprise needs to select projects, with constraints of limited resources over time, to maximize its enterprise objectives, such as profit, capability of research and development, capability of innovation, risk, public relationship,..., etc. This research studied the Project Portfolion Management (PPM) for resource-constrained multiple projects. Based on literature survey, typical decision models and project objectives were identified. An enterprise can select appropriate PPM models according to its business environments to best utilize its resources and to maximize its objectives.