Pseudo-color processing is a technique that maps each of the grey levels of a black and white image into an assigned color. This colored image, when displayed, can make the identification of certain features easier for the observer. The mappings are computationally simple and fast. This makes pseudo-color an attractive technique for use on digital image processing systems that are designed to be used in the interactive mode. This paper will discuss the application of several pseudo-color mapping schemes. Various color maps can give contrast enhancement effects, contouring effects, or grey level mapping (depicting areas of a given grey level). Pseudo-color schemes can also be designed to preserve or remove intensity information. Since the nature of the original black and white image can determine the success or failure of a particular color scheme, it is necessary to find a rational approach to the design and selection of the color maps. The paper will describe some methods of designing color schemes that use ideas from the fields of colorimetry and visual perception.