As the Internet/Intranet/WWW technologies become more and more mature and web-based applications become richer and richer, the application developers are provided with an ideal computing environment to construct WfMSs (workflow management systems). Web-based WfMSs can help business goals to be achieved effectively by means of integrating various distributed resources in an easy to access environment. A web-based general purpose workflow management system named Wowww! is described in this paper, detailing its architecture, the workflow model and the algorithms used for workflow instance execution, the self-learning algorithm for automatic process definition generation, and the strategies to support synchronous cooperation.