The present invention provides a method and system for sharing a browser wherein it is not necessary to install a controller for sharing on a computer in advance. More particularly, a collaboration server is provided for accumulating pages to be shared from a Web server retaining original pages. A collaboration server comprises a CachinManager that accumulates pages dynamically generated on the original Web server for sharing, a CommunicationManager that controls sessions such as communication and participation / quitting among NodeManager controlling a browser on each user machine, an ordinary Web server for downloading facilities for implementing sharing of a Web server and an Embedder that embeds in each page a PageManager for controlling pages. The plural user machines to be shared comprise and existing Web browser capable of running Java and Script, and PageManager embedded in each page. A PageManager comprises two parts, namely, namely, a PageController and a PageCommunicator. A PageController detects changes in a page element, communicates them to another machine by way of a PageCommunicator, and receives changes in a page of another computer and then reflects the same changes to own page element. A PageCommunicator manages communication between a NodeManager and a PageController. A NodeManager cor controlling a browser is provided for each process and manages communication between each PageManager and a server.