The present invention relates to α-amylase variants that are stabilized to dimerization and/or multimerization, in particular at elevated temperatures or high pH, by point mutagenesis of positively polarized or charged or neutral surface amino acids to give more negatively polarized or charged amino acids. The invention further relates to methods of increasing the stability of an α-amylase to dimerization and/or multimerization brought about by electrostatic interactions whereby at least one amino acid residue on the surface of the starting molecule, which makes a neutral or positively polar or charged contribution to the electrostatic potential of said molecule, is replaced with a more negatively polar or negatively charged amino acid residue. The α-amylase variants obtained thereby exhibit better stability to influences of the solvent, increased processivity, and are suited for numerous industrial areas of use, in particular as active ingredients in detergents and cleansers.