Many dyes are known to fade when left exposed to sunlight for prolonged periods. Such photofading is a well known technological phenomenon within the textile industry [1]. In particular, certain applications of textile dyes require higher light fastness quality control than others and this has led to an accepted light fastness scale that facilitates selection of a dye for a given application. In comparison, little is known with certainty about the key scientific factors that govern light stability or about the mechanisms of subsequent degradation [1]. A number of reviews have appeared on the light fastness properties of dyes, and an extremely complex picture emerges used. Furthermore, attempts to simplify by investigating dyes under model conditions in solution tend to be counterproductive, as the experiments are not necessarily representative of dyes bound to textiles. This review attempts to search for a more generic picture by outlining the key principles of light stability and illustrating with particular examples. At the outset it is realized that dyes may be extremely complex, may contain impurities or exist in various states of aggregation, or contain certain substituents that are photoactive in their own right. Nevertheless, by outlining the general principles with selected illustrations, the intention is to accommodate the diverse behavioral patterns and present to the reader a simpler, yet accurate, perspective.