The invention relates to α-amylase variants, which are stabilized with regard to dimerization and/or multimerization by the point mutagenesis of positively polarized or charged or neutral surface amino acids into negatively polarized or charged amino acids. The invention also relates to methods for increasing the stability of an α-amylase with regard to a dimerization and/or multimerization induced by electrostatic interactions, whereby at least one amino acid radical of the starting molecule, which is located on the surface of the molecule and which exerts a neutral or positively polar or charged contribution to the electrostatic potential of the molecule, is replaced by a stronger negatively polar or negatively charged amino acid radical. The α-amylase variants obtained in this manner exhibit an improved processivity and are suited for numerous technical areas of application, particularly for use as active ingredients in detergents and cleansers.