Article describes how preserving antique textiles depends upon not subjecting them to the functional use for which they were intended, and controlling the amount of light to which they are exposed. Light, one of the primary sources of destruction of textiles, causes physical and chemical damage that is cumulative and irreversible. The resistance of a fabric to fading -- its light fastness -- rests on inherent factors (type of dye, preparation, method of application) that are not subject to correction. The collector can slow down inevitable color loss by regulating the amount of light to which a textile is exposed: alternating short display periods at low light levels with longer periods of storage in darkness. Includes chart relating rates of deterioration to light levels. -- AATA