This research discusses knowledge contents needed to build an OLAP system for medical sector, OLAP functionalities from past studies, and a medical intelligence system which is a kind of OLAP. The knowledge requirements which consist of nine contents and OLAP fundamental functionalities are applied to the system. Most past studies have focused on developing a medical data warehouse rather than OLAP. The medical intelligence system supplies health care providers (i.e., doctors, clinicians, researchers and nurses) and non-providers (i.e., managers and business analysts) with multidimensional OLAP functionalities. The system can be used to gain a deeper understanding of specific medical issues. In this research, we focus not on medical data warehouse, but on the technical challenges of designing and implementing an effective medical intelligence system for health care information. An architecture is applied to developing the medical intelligence system for a medical center in order to illustrate its practical usage. Six packages in the developed system are discussed in this research: Explorer, Analyzer, Reporter, Statistician, Visualizer, and Meta Administrator packages. Evaluation of the system and ongoing research directions conclude the research.