Summary form only given. Telepresence is the future of multimedia systems and will allow participants to share professional and private experiences, meetings, games, parties. The concepts of distributed virtual environments are a key technology to implement this telepresence. Using virtual humans within the shared environment is a essential supporting tool for presence. Real-time realistic 3D avatars will be essential in the future, but we will need interactive perceptive actors to populate the virtual worlds. The ultimate objective in creating realistic and believable virtual actors is to build intelligent autonomous virtual humans with adaptation, perception and memory. These actors should be able to act freely and emotionally. Ideally, they should be conscious and unpredictable. But, how far are we from such a ideal situation? Our interactive perceptive actors are able to perceive the virtual world, the people living in this world and in the real world. They may act based on their perception in an autonomous manner. Their intelligence is constrained and limited to the results obtained in the development of new methods of artificial intelligence. However, the representation under the form of virtual actors is a way of visually evaluating the progress. In the future, we may expect to meet intelligent actors able to learn or understand a few situations