Book excerpt: ABSTRACT: As the global marketplace becomes more and more competitive, business organizations often need to team up and operate as a virtual enterprise in order to utilize the best of their resources for achieving their common business goals. Since the business environment of a virtual enterprise is highly dynamic, it is necessary to develop a workflow management technology that is capable of handling dynamic workflows across enterprise boundaries. This dissertation describes a dynamic workflow model and a dynamic workflow management system for modeling and controlling the execution of inter-organizational business processes. In this work, all the sharable tasks performed by people or automated systems in a virtual enterprise are defined and published as e-services. The business process models of inter-organizational workflows are defined in terms of, among other things, compositions of e-services provided by the participating organizations. A dynamic workflow model (DWM) is introduced to enable the specification of dynamic properties associated with a business process model. It extends the underlying model of the Workflow Management Coalition's Workflow Process Definition Language (WPDL) by adding connectors, events, triggers, and rules as its modeling constructs, encapsulating activity definitions and allowing e-service requests to be included as a part of the activity specification. The workflow management system makes use of a business event and rule server to trigger business rules during the enactment of a workflow process model to enforce business constraints and policies and/or to modify the process model at run-time. We also introduce a constraint-based, dynamic service binding mechanism to dynamically bind e-service requests to e-services that satisfy some constraint specifications.