Many animals, including humans, have evolved the use of color vision. It cannot be assumed, however, that animals perceive or detect color in the same way that humans do. This study aims to both test the feasibility of goldfish as a viable model for studying animal color vision, and to address questions about perception of color in nature by animals. We are particularly interested in assessing the role that color contrast – the difference between the color of an object and its background – plays in making objects more or less visible. We are also interested determining whether goldfish exhibit color categorization: the tendency to perceive certain different colors as fundamentally similar, and if it is similar to the same process in humans. We trained goldfish to feed from a plastic holder that contains a brightly colored mark near the food release point. Our goldfish rapidly learned to identify the color orange with a food reward. We are now using this basic response to test how different stimulus/background color combinations alter response probability. We also plan to test categorization by measuring the tendency to approach novel colors that differ from the training color in various ways.