Abstract: Permanently stain resistant nylon and cellulosic fibers, and a method to impart permanent stain resistance to polyamide or cellulosic fibers, by covalently binding a stain resistant composition to a linking compound that has been covalently attached to the fiber are disclosed. This invention represents a significant advance in the art of textile treatments in that the covalently linked stain resist treatment is not removed after a series of alkaline shampooins. This invention is particularly useful in the preparation of commercial grade carpets for heavy traffic areas that will not lose their stain resistance after frequent shampooing.