We studied color vision in 32 patients with autosomal recessive achromatopsia. Color matching revealed complete achromatopsia (rod monochromacy) in ten patients (Group I) and incomplete achromatopsia in the remaining twenty-two patients. Amongst the incomplete achromats, were three groups distinguishable by their color matching. Patients in Group II were dichromats; their color matches were mediated by rods and MWS (middle-wavelength sensitive) cones. Patients in Groups III and IV were trichromats. Color matches of patients in Group III were mediated by rods, LWS (long-wavelength sensitive) cones and MWS cones. Group III patients showed no evidence of SWS (short-wavelength sensitive) cones. Color matches of patients in Group IV were mediated by rods, LWS cones and SWS cones; color matching did not reveal MWS cones.