Abstract: A computer system comprising processing means and a display, the processing means being arranged in use to implement a Microsoft Windows™ operating system under which a management window can be displayed on said display such that it can be navigated using a web browser. The management window has a first frame containing a web style page and a second frame displaying one or more systems which can be controlled by the user, wherein upon selection of one of the systems by the user the current page displayed in said first frame is replaced by a page specific to the selected system.