A hard surface detergent composition is provided, said composition comprising a peroxygen bleach capable of exhibiting bleaching properties at a pH of below (9), and an amino ketone or derivative thereof bleach activator, and wherein a l%wt solution in distilled water at 25 DEG C of the composition has a pH lower than (9). Potassium monopersulphate is the preferred bleach compound and diethyl amino acetone or derivative thereof is the preferred bleach activator. The compositions exhibit good bleaching performance at pHs of less than (9).