Communication from applications may be carried in XML-based events through sockets, Web services, JMS, HTTP, telnet channels, and the like to an OPC client. The OPC client may include an event engine configured to process the XML-based events, and convert them to appropriate COM/DCOM API invocations. In some embodiments, the OPC client buffers collected data from the COM/DCOM API, and transmits the buffered data in an XML event to an application based on a subscription time schedule and/or value condition. The OPC client allows service oriented event-driven applications to interact with industry devices remotely via the open architecture provided by the OPC specification using a business level language syntax.