I motivate and defend a previously underdeveloped functionalist account of the metaphysics of color, a view that I call ‘quality-space functionalism’ about color. Although other theorists have proposed varieties of color functionalism, this view differs from such accounts insofar as it identifies and individuates colors by their relative locations within a particular kind of so-called ‘quality space’ that reflects creatures’ capacities to discriminate visually among stimuli. My arguments for this view of color are abductive: I propose that quality-space functionalism best (...) captures our commonsense conception of color, fits with many experimental findings, coheres with the phenomenology of color experience, and avoids many issues for standard theories of color such as color physicalism and color relationalism. (shrink)