Information systems are one of the most important tools for organizations to conduct business today. The dependency of organizational functions to information systems makes them critical for the people using them. So becomes the impact of failure or success of information systems more significant in organizations. The initial task for information systems designers is to appreciate this real life situation and understand various aspects of information systems and their evolution over the past decades.Information system design is a detailed process which has to be planned and implemented with great care not only for, but also with the business experts and users. Designers and users should be aware of the problems, requirements within the organizational context. In this thesis, we will describe and discuss various information systems in organizations. Different information system types will be given.Database management systems (or databases in organizations) are the essential parts of information systems. A "good" information system is surely backed up with a "good" database behind it. Designing a "good" database systems is the critical part of the process. Following structural and well defined methods on database design is something we need in today in organizations. We will present, further in this thesis, various database management systems and database types. Relational model is the most widely used database management system today. We will study various relational database model concepts which will be a base for our management information system database design. We will follow various design and refinement methodologies to end-up with a well documented and refined relational database model. During our design we will utilize a sophisticated database design tool. We will use the database design tool Sybase PowerDesigner. Our design will be modeling a man-power planning database ..