The state-of-the-art of using colors-coded video displays in modern day simulators necessitates looking at the human factors elements and the efficacy of whether the use of color is necessary at the instructor operator station. This paper covers some fundamental aspects of the physiology of color vision and the human factors considerations that need to be addressed in the design of video displays. Experiences encountered by Sperry in its design of CRT displays have led to a preliminary color convention. Finally, a list of recommendations and suggestions are provided as a guide in the design of color-coded displays.