The report describes the results of a study to develop a graphical symbology and logic diagraming technique for use as a training aid. This work is addressed to the need for a language which describes the logical relationships among task components and the interactions between man and machine in advanced computer-based information systems. Symbols and a logic diagraming technique were developed and refined by utilization with several different types of tasks. This 'language' has been found to be useful for the following purposes: (a) to supplement written instruction manuals, (b) as an instructional tool without text, and (c) as a performance aid when displayed directly on an operational console. A step-by-step methodology for constructing logic flow diagrams is presented, and applications are discussed.