The present invention provides a communication assistance process that is performed by a communication assistance device connected to a plurality of user terminals via a network. During a communication (or video) conference call, when assistance data associated with a topic in the conference is provided to a plurality of user terminals in the form of a voice data, the communication assistance process adjusts the sound volume of voice data in the assistance data if it was determined that voice data is included in the communication data received from the plurality of user terminals, and if voice data is also included in the assistance data, the assistance data that includes sound volume adjusted voice data is then provided to the plurality of user terminals. Accordingly, the communication assistance process allows communications in a conference system to proceed smoothly.