A computer-implemented collaborative editing method includes receiving input from a user of a browser-based document editing application on a document displayed by the application; identifying a current location in the document for a cursor of a first user executing the application; receiving from a central server system data that reflects changes made to the document by one or more users other than the first user and current positions in the document of cursors for the one or more other user; updating a document model stored on a computing device that is executing the browser-based application and rendering at least a portion of the model to the browser; and rendering the current positions of the cursors for the one or more other users to the browser.