A stabilizer combination, mainly for PVC, is described, comprisingA) at least one compound of formula I ##STR1## wherein R*.sub.1 and R*.sub.2 are each independently of the other C.sub.1 -C.sub.12 alkyl, C.sub.3 -C.sub.6 lkenyl, C.sub.5 -C.sub.8 cycloalkyl that is unsubstituted or substituted by from 1 to 3 C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, C.sub.5 -C.sub.8 cycloalkyl or by hydroxy groups or by chlorine atoms, or C.sub.7 -C.sub.9 phenylalkyl that is unsubstituted or substituted at the phenyl ring by from 1 to 3 C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, C.sub.5 -C.sub.8 cycloalkyl or by hydroxy groups or chlorine atoms,and R*.sub.1 and R*.sub.2 may additionally be hydrogen and C.sub.1 -C.sub.12 alkyl, and Y is S or O, andB) at least one compound from the following groups:B1) perchlorate compounds,B2) glycidyl compounds,B3) beta-diketones and beta-keto esters,B4) dihydropyridines and polydihydropyridines,B5) polyols and disaccharide alcohols,B6) sterically hindered amines (tetraalkylpiperidine compounds),B7) alkali aluminosilicates (zeolites),B8) hydrotalcites,B9) alkali aluminocarbonates (dawsonites),B10) alkali- (or alkaline earth-) carboxylates,-(bi)carbonates or -hydroxides,B11) antioxidants and lubricants andB12) organotin stabilizers.