A multifunction display provides the flight crew with access to a mix of information. The challenge for the crew, the designer, and the certification agencies, is to determine if the human interface to this mix can be understood under normal and abnormal conditions. The technical capabilities of signal processing and displays permit endless information combinations to exist. However, human performance and mental processing capabilities impose significant challenges in designing the display and controller interface. For the crews to be successful, they ultimately need to obtain an increase in their level of situational knowledge from the flow of information that a multifunction display provides.