Fastness has usually been subordinated to uniform level dyeings. However, modern dyed leathers can compare favorably to textiles in fastness to light, to soaping, and to solvent cleaning. They may be combined in multicolored combinations that can be subjected to normal cleansing operations and to light without fear of stain or loss in color. A nearly complete range of colors is available. Limitations are the relatively low temperatues used in leather dyeing (120-150 degrees F) the sensitivity of leather to highly alkaline solutions, and the necessity of using a raw material which varies widely in its physical character and in the nature of the tanning process. Most leather is now chrome tanned and is resistant to conditions that would destroy vegetable tanned leather. Vat dyes, used on textiles, have good fastness. Relatively colorfast 1) Direct and chrome dyes, 2) azoic or naphthol dyes, 3) leuco ester vat dyes and 4) sulfur dyes have been adapted for use on leather. These four dye methods supplement each other. For full shades, the chrome and direct colors with resin aftertreatment produce the gratest range of color; the naphthols produce full brilliant shades especially in the reds and oranges; the sulfurs produce excellent tans, greens, and grays; the leuco ester vats produce excellent pastels and medium shades.