Abstract: A method is disclosed for the preparation of a flowable and pumpable solution containing at least 70 weight percent of betaine of the following general formula ##STR1## in which R.sup.1 is the alkyl group of a fatty acid or a fatty acid mixture with an average of 6 to 18 carbon atoms, R.sup.2 and R.sup.3 are the same or different and represent an alkyl or a hydroxyalkyl group with 1 to 4 carbon atoms, x has a value of 2 or 3 and y a value of 1,2,3 or 4.The solutions prepared by the method have a viscosity of not more than 25,000 mPas at 25.degree. C., as a result of which the compounding of the solutions to liquid soaps, shampoos, shower gels and other cosmetic preparations is facilitated, while at the same time the costs of dispensing, transporting and warehousing are reduced. Solutions containing at least 70 percent by weight of the above betaines are also disclosed.