Abstract: The invention provides a process for synthesising functionalised chain transfer polymers of Formula (1) or Formula (2) using thiocarbonyl thio compounds as chain transfer agents. Why R1 is a moiety comprising a functional group; Q is obtained from an olefinically unsaturated monomer; R? is selected from the group consisting of alkyl, substituted alkyl, alkoxy, substituted alkoxy, an aromatic saturated or unsaturated carbocyclic or heterocyclic ring, optionally substituted with one or more substituents, amino alkyl, cyanoalkyl, hydroxylalkyl, saturated and unsaturated amido; an organometallic species, a polymer chain and any of the foregoing substituted with one or more CN or OH groups; q=an integer of at least 2; p=an integer of at least 1. Chain transfer agents and polymers produced by the method are also provided.