This is a Masters thesis work in Computer Science at the University of Stockholm, accomplished at SICS (Swedish Institute of Computer Science) during autumn and winter 1988-89. In the area of Human-Computer Interaction, HCI, there is currently a lot of research. We are discussing some important aspects of HCI, mainly concerning design of graphical editors, as WYSIWYG, event driven actions, undo-mechanism and menu-arrangements. The report also describes a design and implementation of some graphical editors used in LOGGIE. These editors are used to design symbols, windows, menus, etc. to be used in LOGGIE.