A new RAFT agent leaving group based on a triazole moiety is introduced. The triazole moiety plays an active role in the stabilization of the intermediate radical, comparable to the phenyl group in a benzyl leaving group. The newly developed leaving group allows easy conjugation to a large variety of substrates where the triazole linking group is hydrolytically stable. Good control is reported in the polymerizations of vinyl acetate, N-vinylpyrrolidone, n-butyl acrylate, and styrene. The versatility of the method is exemplified by linking the triazole to a phenyl and to an oligosaccharide substrate. Overall, this new RAFT agent leaving group is a useful addition to the limited set of leaving groups reported in literature. © 2009 American Chemical Society.