Color perception, color usage, and safety colors are important aspects of illuminating engineering. Their practical scope extends beyond illuminance, luminous density (and their contrasts), glare evaluations, and color rendering indices of light sources. In view of the strongly esthetically and psychologically effective components in color perception and illuminating engineering oriented primarily one-sidedly towards the ″constitutive importance″ of brightness, too little attention has so far been paid to color in the field of illuminating engineering. Some progress in this respect is reported in the article.