The invention relates to a method for the production of a polymer (P) comprising amide and ester groups, whereby, in a first step, a homo- or co-polymer (P1) of (meth)acrylic acid is reacted with a monohydroxy compound (E) at a temperature of up to 200.degree. C., such that, in addition to ester groups, anhydride groups are formed and, in a second step, the anhydride groups formed in the first step are reacted with a monoamine compound (A) at temperatures significantly below 100.degree. C. The invention further relates to polymers produced by the above method, the use thereof in hydraulic-setting compositions and said hydraulic-setting compositions before and after hardening by addition of water.