A user interface system supports flexible user navigation and item selection and manipulation in a hierarchical data structure representation. The user interface system facilitates selection of a plurality of items from a display of hierarchically organized items. The user interface system includes a user interface image generator for providing data representing a displayable image showing a hierarchical organization of user selectable icons visually identifying whether the selectable icons are currently selected. The hierarchical organization of icons links a parent icon representing a first group of data items with multiple child icons representing corresponding data items of the first group and an individual one of the child icons links to a second group of grandchild icons representing a corresponding second group of data items. The user interface system also includes a user interface command processor for initiating selection of direct ancestor icons of the grandchild icon comprising the parent icon and the individual one of the child icons excluding others of the child icons, in response to user activation of a mode of selection of the grandchild icon.