Abstract: Described are an online meeting system and method for integrating a third-party system with the online meeting system. A service provider interface (SPI) defines procedures for communicating with a meeting services application of the online meeting system. Each software module implements the procedures of the SPI to perform meeting-related operations customized in accordance with the third-party system when called by the meeting service application. Called SPI procedures include two types. One type notifies a software module of a proposed transaction of an event in the online meeting system, to enable the software module to perform the meeting-related operation before the event occurs. A second type notifies a software module of an event that has occurred in the online meeting system, to enable the software module to perform the meeting-related operation in response to the occurrence of that event.