Both from the perspective of practitioners as well as from an academic point of view, e-government has gained considerable momentum in the past years. However, in order to create a sound e-government body of knowledge much research work still has to be done. This paper reports on the findings of the use of the structured-case approach to investigate the success factors for e-government initiatives. A total of fifteen case studies were conducted in seven European countries. The paper outlines the contribution of the structured-case approach to build e-government theories. The paper concludes that the structured-case approach demonstrates the process of knowledge and theory building because it clearly points out the linkage between the data collected and the conclusions drawn. Hence, the application of the structured-case approach assures scientific rigor-an element that is often missed or done poorly in IS case study research.