This article presents the utilization of molecular amplification to visualize the molecular architecture of arborescent (tree-like) polystyrenes (arbPSs) using atomic force microscopy (AFM). arbPSs with Mn > 80,000 g/mol were synthesized via initiator-monomer-type (inimer) RAFT polymerization of styrene mediated by 4-vinylbenzyl dithiobenzoate in bulk. These arbPS were then used as macrochain transfer agents for polymerization of vinylbenzyl chloride (VBCl) to give arborescent poly(styrene-block-vinylbenzyl chloride) (arbPS-b-VBCl). Poly(styryl) diphenylethyl lithium (Mn = 11,000 g/mol) was then grafted onto the VBCl units of the arbPS-b-VBCl. The Mn of the amplified arbPSs increased over >10 million g/mol, exceeding the exclusion limit of our size exclusion chromatography equipment. AFM confirmed the proposed branches on branches architecture in the samples, together with lesser branched species. (c) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012