The first sonochemically induced reversible addition-fragmentation chain transfer by the polymerization-induced self-assembly process (Sono-RAFT-PISA) has been investigated. High-frequency ultrasound (490 kHz, 40 W) was applied for the controlled polymerization of N-isopropylacrylamide (NIPAM) in aqueous dispersion via the Sono-RAFT-PISA technique using poly(poly-(ethylene glycol) methyl ether acrylate) (PPEGA) as both macromolecular chain transfer agent and surfactant (macro-transurf). The synthesis of PPEGA-b-PNIPAM copolymers in aqueous media at 20 degrees C (DPn,NIPAM = 204) was found to reach total NIPAM conversion in a short time (60 min.) with narrow molecular weight distribution (D < 1.26). Furthermore, PNIPAM-based spherical nanogels (D-h <= 69 nm, pdi <= 0.26) were successfully synthesized by Sono-RAFT-PISA (aqueous dispersion, 45 degrees C), qualifying as a highly "green" method due to the complete monomer conversion, absence of organic initiator, of residues, and to the unique use of water as initiator and solvent (inisolv).