An internet website which presents a hierarchical menu structure to users includes a personalization engine 14 to automatically modify the menu structure for each user at least according to that user's previous browsing history at the site. In one embodiment the engine 14 provides, as menu options for a selected menu page of the hierarchical menu, a plurality of the most probable links which the user may wish to reach from the selected menu page. In another embodiment there are provided, as additional menu options for a particular menu page, a plurality of links which are similar, as determined by meeting a predetermined similarity metric, to menu options present on the particular menu page other than through meeting the similarity metric.