Abstract. In this paper, we propose an Internet-based information correlation service called Correlation DialTone that is designed to increase the utility of event-based information. This service concept opens new business opportunities for Internet-based information services, such as Stock Market Correlation DialTone, Health Care Correlation DialTone, and Home Security Correlation DialTone. We present the component-based architecture of the distributed event correlation service and its component services: correlation subscription, data mediation, event parsing, event correlation, event delivery, and event notification services. We describe process/knowledge representation models and implementation of the distributed correlation service using CORBA, XML, Java, and model-based reasoning technologies. In addition to discussing the concept, the proposed service architecture, and the candidate applications, we also describe an implementation of a distributed event correlation system supporting the Correlation DialTone service.