The invention relates to optically transparent compositions containing hydrophobic silicone oil and alkyl ether carboxylates that are useful e.g. as a hair treatment composition such as a shampoo. In particular, it provides an optically transparent composition comprising (a) a hydrophobic silicone oil; and (b) an alkyl ether carboxylate derived from alkanols having 6 to 22 carbon atoms; wherein the weight ratio of component (b) to component (a) is in the range of 1:1 to 20:1. The composition preferably also contains anionic surfactants as component (c), the total amount of the components (b) and (c) being preferably in the range of 10-25 wt.-% with respect to the total weight of the composition. The invention also provides a method for preparing the above composition.