An interactive display apparatus and method for a plant operating at a plurality of process parametes from which a current plant status can be calculated, and from which symptoms can be diagnosed which indicate the existence of transient conditions of plant status for which mitigating action must be taken within a time interval, utilize a central computer for storing all appropriate mitigating actions which should be taken upon the occurrence of a symptom. The computer is also programmed with algorithms for selecting and prioritizing mitigating actions that are appropriate. A display is connected to the computer for displaying the list of mitigating actions which are appropriate for a symptom diagnosed by the central computer. Sets of symptom indicators and extreme action indicators are also driven by the computer. Each symptom is represented by a separate card which can be independently illuminated to indicate the existence of that symptom. If the symptom is not corrected by appropriate mitigating action within an implied time interval, an extreme action indicator card is lit from along a plurality of extreme action indicators. This indicates to the plant personnel that now extreme action is needed. The central computer also calculates which extreme actions are needed from a list of stored extreme actions. These too are displayed to the plant operator. To help the plant operator on determining the effects of mitigating actions and the ongoing status of the plant, a separate display connected to the central computer, displays current plant status.