A method, system and apparatus for previewing documents on a computer system, the method comprising the steps of:--displaying a main document (102) which contains a hyperlink (104); and--in response to an indication (106) of the hyperlink being received by the computer system, displaying a preview document (108) which document being that referred to by the hyperlink whilst retaining the display of the main document, so that the document referred to by the hyperlink may be previewed.