The present invention provides aqueous compositions comprising, as well as water, 75% to 90% by weight of alkyl polyethylene glycol ether sulfates which are a mixture of compounds of formula (1) R.sup.1--O--(CH.sub.2--CH.sub.2--O).sub.x--SO.sub.3M (1) where R.sup.1 is a branched alkyl or alkenyl group having 8 to 14 carbon atoms and at least one tertiary carbon atom, x is from 3 to 15, M is an alkali metal ion or an ammonium ion,with compounds of formula (2) R.sup.2--O--(CH.sub.2--CH.sub.2--O).sub.y--SO.sub.3M' (2) where R.sup.2 is a linear alkyl or alkenyl group having 8 to 14 carbon atoms, y is from 3 to 15, M' is an alkali metal ion or an ammonium ion,wherein the mixing ratio of compounds of formulae (1) and (2) is chosen such that the compounds of formula (1) comprise at least 10% by weight and at most 99% by weight of the total amount of compounds of formulae (1) and (2).