Abstract
Web sites are complex systems. They evolve all the time and are hard to understand and be maintained. This paper discusses some issues and challenges related to web site development and maintenance. An evolutionary three-tier web site architecture is presented based on our experiences in building and maintaining web-based public utility management systems. In the current public utility domain, the coexistence of regulated and deregulated markets and diverse business rules bring many challenges to software engineers to build extensible and maintainable web-based systems. New technologies provide opportunities to meet these requirements. However, how to adopt new technologies appropriately becomes another issue. Some design and implementation tradeoffs, as well as some lessons learned are considered in this paper.