Abstract: The present invention relates to a stabilizer system for polymers containing halogen, comprising an alkaline earth metal double carbonate of the formula (A) (M1O)m*(M2O)n?m*(CO2)o*(H2O)p??(A) where M1 and M2=various alkaline earth metals; m=from 0.9 to 1.1; n=from 1.9 to 2.1 and p=from 0 to 2.1; or n=from 3.9 to 4.1, and p=from 0 to 4.1; o=from 0 to 1.1 and at least one of the compounds selected from the group consisting of (B) and (C), where (B) is at least one nitrogen-containing organic compound selected from the group consisting of (B1) and (B2), where (B1) is a tert-alkanolamine and (B2) is an enaminone or a urea, and (C) is an alkaline earth metal aluminohydroxocarbonate of the formula (C) (M1?xZnx)yAl2(OH)4+2yCO3*zH2O??(C) where M=magnesium or/and calcium; x=from 0 to 0.5; y=from 2 to 8, and z=from 0 to 12. The present invention further relates to compositions and articles comprising said stabilizer systems, and to processes for stabilizing a polymer containing halogen.