The invention relates to the use of an ampholyte copolymer as a colloidal stabilizer in the preparation of aminoplast core-shell microcapsules containing an active material, wherein the ampholyte copolymer comprises:2 to 99 mol % of cationic monomer having at least one quaternary ammonium group,1 to 98 mol % of acrylic based monomer,0 to 97 mol % of non-ionic monomer,and wherein the ampholyte copolymer has more cationic charges than anionic charges, wherein the cationic charges of the ampholyte copolymer are exclusively due to the at least one quaternary ammonium group of the cationic monomer.