In this paper, we describe an approach to audiovisual data modeling for multimedia integration and synchronization. The approach chosen consists in using description tools from Multimedia Description Schemes of standard MPEG-7 to describe audiovisual contents and in integrating these description models into a multimedia integration and synchronization model close to SMIL. The resulting model provides relevant specification tools for the fine integration of multimedia fragments into multimedia presentations. An authoring environment illustrates the authoring features that can be obtained thanks to these integrated models. Categories and Subject Descriptors D.3.3 [Information Interfaces And Presentation]: Multimedia Information Systems – Evaluation/methodology, Hypertext navigation and maps, Video. General Terms Design, Documentation, Experimentation, Languages. Keywords Multimedia document authoring, Fine-grained synchronization, Content description, MPEG-7, Multimedia description sc...