Abstract: Three dimensional models having one or more model components stored in model databases, accessed by servers, and being viewed interactively from client computers are processed for transmission over a network. A model hierarchy is built with one or more nodes, by clustering together one or more of the model components based on one or more clustering criteria. One or more representations are associated with each node in the hierarchy. A cost function is associated with the model hierarchy and used to determine a cost of each representation at each node. A visibility of each node in the hierarchy is evaluated and associated with the respective node. A contribution of each node to an image of the 3D model to be rendered by one or more of the clients is evaluated. The 3D model hierarchy is traversed to select one or more of the representations to be transmitted to the client using a prioritization scheme that accounts for the visibility and contribution of each respective nodes.