Over the years the use of on-line portal systems has increased tremendously among educational institutions. However, a portal that is not easy to use is more likely to drive users away than attract them. If such a portal is the gate to some commercial products, it can become a stumbling block to the success of the business it is meant to promote. This book stresses the need to design and implement effective portal systems that recognize the central role of usability. The book presents a practical model for conducting evaluation of portal systems using a case study approach. Two on-line portal systems have been evaluated and the results are clearly explained in a separate chapter. This approach also highlights important insights that are recognizable from a typical review and explains how such feed back can contribute to effective post implementation review. In this book readers can find information that is useful to them whether they are designers or business owners. Using information in this book, business owners can actively participate in the evaluation of their portals in order to ensure that the portal does not produce undesirable effects due to pitfalls of poor design.