Anionic, hydrophobic polysaccharides useful as soil release agents in detergent compositions are graft copolymers of a polysaccharide having anionic substituents with an ethylenically unsaturated monomer, the copolymer having a polysaccharide backbone carrying grafted hydrophobic vinyl polymeric groups derived from the ethylenically unsaturated monomer, and anionic substituents. The polymers exhibit enhanced release of both oily and particulate soil from both polyester and cotton.