AbstractMunsell started to base his color‐order system on measured physical quantities, but it came to represent the order of colors us they ure perceived. The hue circle represents fundamental facts about color vision. The Munsell hue circle has anomalous placement of blue and the use ($five principal hues does not relate to color vision nor applied color science. A reoriented hue circle, labeled with the additive and subtractive primariesblue,green, red, yellow, magentu, and cyan‐but retaining the existing Munsell hue spacing and sectors is proposed.The primury hue circle relates to vision and color‐reproduction processes, so it should exert a unifying influence on color .science. 0 1993 John Wi1ey .&Sons.