The present invention relates to carbonate blend compositions demonstrating improved environmental stress crack resistance in combination with an excellent blend of impact, thermal, and physical properties. Said carbonate blend composition comprises a polycarbonate, a polyester, and a silicon-containing graft (co)polymer having a core-shell morphology, comprising a shell that contains (co)polymerized alkyl(meth)acrylate and glycidyl methacrylate grafted to a composite rubber core that contains polyorganosiloxane and poly(meth)alkyl acrylate components and methods to make said compositions.