The present invention provides an aqueous effervescent liquid detergent composition which upon contact with water provides effervescent action, and which comprises at least 5% by weight of a surfactant and from 0.1 to less than 3% by weight of a volatile organic solvent selected from pentane, hexane, cyclohexane and diethylether. Said solvent is present in sufficient amount to provide the effervescent action, and has a higher solubility in an aqueous surfactant-containing composition than in water, the boiling point of said solvent being lower than the typical temperature during the washing process.