The invention relates to amide-containing polymers of the general formula (I)A-X—CO—(CH2)2—NR1—R2—[Y—R3—Y—R4)a—B (I)and also their salts with carboxylic acids, phosphoric esters and sulphonic acids. The invention further relates to processes for preparing the amide-containing polymers and to their use as rheology control agents.