In polymer chemistry, reversible-deactivation radical polymerizations (RDRPs) are members of the class of reversible-deactivation polymerizations which exhibit much of the character of living polymerizations, but cannot be categorized as such as they are not without chain transfer or chain termination reactions. 
Several different names have been used in literature, which are:
*Living radical polymerization
*Living free radical polymerization
*Controlled/"living" radical polymerization
*Controlled radical polymerization
*Reversible deactivation radical polymerization
Though the term "living" radical polymerization was used in early days, it has been discouraged by IUPAC, because radical polymerization cannot be a truly living process due to unavoidable termination reactions between two radicals. The commonly-used term controlled radical polymerization is permitted, but reversible-deactivation radical polymerization or controlled reversible-deactivation radical polymerization (RDRP) is recommended.