Water-soluble copolymers based on a) 50 to 97% by weight of one or more non-ionic, ethylenically unsaturated monomers containing amide groups, b) 0.1 to 10% by weight of one or more ethylenically unsaturated monomers containing silane groups c) 1 to 30% by weight of one or more ionic, ethylenically unsaturated monomers and optionally one or more further ethylenically unsaturated monomers, are useful as protective colloids for inorganic particle and water-insoluble polymer particle dispersions. wherein the figures in % by weight add up to 100% by weight.