Abstract: A system facilitates co-use of an interface by multiple client computer, such as co-browsing of a webpage. A first user computer using an interface transfers a state of the interface to a server, which uses the state to recreate the interface in a virtual client executed by the server. The interface is rendered on a virtual screen and images of the screen are transmitted to the first user computer and one or more second user computers performing co-use with the first user computer. For example, a browser rendering a webpage on a first computer transmits session data and cookies associated with the webpage to a virtual browser executing on a server system. The virtual browser retrieves the webpage and uses the session data and cookies to render the webpage on the virtual screen.