On many types of leather, and especially on light leathers, coatings are applied for surface effects, for instance, to give more uniform appearance or to modify the color gloss. These coatings may be uncolored, or colored by dyestuffs or pigments, or both. In addition to these decorative effects, there are effects on the permeability of the leather: nitrocellulose and shellac finishes have been reported by Innes to retard the absorption of atmospheric acid by leather and they have a pronounced waterproofing effect. Finishing coatings in general have a considerable effect on the air permeability of the leather, and also reduce its water vapor permeability to extents which vary according to the type of finish. The principles of formulation of finishes for leather are in many respects similar to those which are applicable to paints and varnishes in general, and there is therefore much in the literature of the paint and varnish industry which is relevant to them. A selection of text books from this literature is included in the references.