Abstract: The invention relates to a network-distributed document collaboration interface for document review sessions that permits multiple participants to view, markup, and annotate a document simultaneously and in real-time. Both synchronous and asynchronous modes of document collaboration are possible. A network-based application permits the centralized control of documents and collaboration sessions to distributed participants. The document collaboration system also permits saving, retrieving, resuming, and replaying document review sessions and supports concurrent real-time audio, video, and text-based meetings.