In one aspect the invention relates to aqueous detergent compositions and in a second aspect to bleach compositions both containing hydrogen peroxide and both particularised or modified by the presence of isopropyl alcohol as part of the stabiliser system therefor. In a third aspect the invention relates to premixes containing 20 to 35 % hydrogen peroxide, water, aliphatic alcohol, phosphonate and preferably a polyhydroxycarboxylate, which can be augmented by the other components of the detergent/bleach compositions and if necessary diluted without any risk of passing through hazardous intermediate compositions inadvertantly.