The Internet is fast becoming the standard environment for client-server applications that involve multiple users. The proliferation of Internet-based application development tools opens new doors to transportation researchers who work in real-time decision support system (DSS) development. In the 1990s, one of the most important problems in advanced transportation management systems research was the development of better incident management systems. Although the incident management process has been well studied, the development of real-time DSSs that can be used by all the involved agencies remains a challenging area of transportation engineering research. Existing incident management systems are developed on various traditional computing platforms, including UNIX and Windows. However, with the advent of the World Wide Web and Internet-based programming tools such as Java, it is possible to develop platform independent decision support tools for the incident management agencies. Web-based support tools offer an invaluable opportunity to develop next-generation online decision support tools for real-time traffic management. The applicability of Web-based tools to the development of online DSSs for incident management is explored and demonstrated, and a prototype incident management DSS that has most of the capabilities of similar UNIX-based DSSs is developed and tested. Briefly described are the implementation and development of a prototype wide-area incident management system using Web-based tools.