Business and enterprise management processes become more and more event-driven. Being event-driven means that processes rely on receiving events to monitor the execution progress, and issuing events to initiate its next stages. What is more important, being event-driven enables these processes to become more active and flexible. There is a paradigm shift today from passive processes to active ones (based on push of information rather than on pull of information and knowledge). Also the management of business processes needs to be flexible, i.e, to adapt to ad hoc changes (events) during operations. All these requirements suggest use of Complex Event Processing (i.e., event patterns, event pattern rules, and event constraints) for realising event-driven business processes. We implement these concepts in a completely logical framework using Concurrent Transaction Logic ( C T R). Particularly, C T R is used for specifying, reasoning, and executing event-driven activities.