Stable thiol-ene compositions are provided which comprise a polythiol, a polyene and a stabilizer system comprising an alkenyl substituted phenolic compound having a formula: ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are independently selected from the group consisting of H, OR, a C.sub.1 -C.sub.8 alkyl, substituted alkyl, alkenyl or substituted alkenyl, a C.sub.6 -C.sub.20 aryl or substituted aryl, or a cyano group; R.sup.4 is H, R, OR, halogen, COR, COOR, or SR; R.sup.5 is OH, OR, OCOR, OCOOR, OCONHR, or OTMS; R is a C.sub.1 -C.sub.6 alkyl, a cycloalkyl, or a C.sub.6 -C.sub.20 caryl or substituted aryl; x and y are 1, 2, or 3; z is 0, 1, or 2; and x+y+z=2, 3, or 4; or a formula: ##STR2## where x, y, z, w, R.sup.1 R.sup.2 R.sup.3, R.sup.4 and R.sup.5 are defined as above, except that x+y+z=2-6, and R.sup.6 is CH.sub.2, C(CH.sub.3).sub.2, O, S, or SO.sub.2 ; and one or more compounds selected from the group consisting of a free radical scavenger, a hindered phenolic antioxidant and a hydroxylamine derivative.