Process for preparing aqueous, flowable, highly concentrated solutions of betaines.

Process for the preparation of aqueous solutions, that is preferably free of organic solvents, flowable and pumpable, highly concentrated betaine of the general formula (III) ** ** see formula wherein R3 is the alkyl radical a fatty acid, which may optionally be branched, may optionally contain multiple bonds and may optionally contain hydroxyl groups, R4, R5 are radicals identical or different alkyl having 1 to 4 carbon atoms, m can be 1 to 3 and y may be 1 , 2, 3, containing betaines of at least 32% by weight by quaternization of compounds containing tertiary amine nitrogen with omega-halogeno-carboxylic, according to known procedures, wherein the reaction mixture, before or during the quaternization reaction is added to 0, 1 to <3% by weight, preferably from 0, 1 to 1% by weight based on the final product, or no micellar thickeners or more.