Cu(0)-wire/Me-6-TREN is a well established catalyst for living radical polymerization via SET-LRP Here, it is demonstrated that this polymerization is not Just living, but it is in fact the first example of immortal living radical polymerization The immortality of SET-LRP mediated with Cu(0) wire was demonstrated by attempting, in an unsuccessful way, to irreversible interrupt multiple times the polymerization via exposure to O-7 from air SET-LRP indeed stopped each time when the reaction mixture was exposed to air However, the SET-LRP reaction, was restarted each time after resealing the reaction vessel and reestablishing the catalytic cycle with the same Cu(0) wire, to produce the same conversion as in the conventional uninterrupted SET-LRP process Despite the interruption by O-2, the reactivated SET-LRP had a good control of molecular weight, molecular weight evolution, and molecular weight distribution, with perfect retention of chain-end fidelity (C) 2010 Wiley Periodicals, Inc J Polym Sci Part A Polym Chem 48 2716-2721, 2010