Biopolymers such as proteins and nucleic acids are the key building blocks of life. Synthetic polymers have nevertheless revolutionised everyday life through their robust synthetic accessibility. Combining the unmatched functionality of biopolymers with the robustness of tailorable synthetic polymers enables the possibility to design new materials ad hoc for an array of applications, including catalysis and degradation. Combinations of natural polymers such as peptides with synthetic polymers are, however, limited to tethering peptides onto the side chains or chain ends of the latter. This synthetic limitation is a critical restraint, considering that the function of biopolymers is programmed into the sequence of their main chain. Work at the Queensland University of Technology’s Soft Matter Materials Laboratory led by ARC DECRA Fellow Hendrik Frisch and PhD student Federica Sbordone reports the radical copolymerisation of peptides and synthetic comonomers yielding synthetic polymers with defined peptide sequences embedded into their main chain (Sbordone F., Veskova J., Richardson B., Do P.T., Micallef A., Frisch H. J. Am. Chem. Soc. 2023, 145, 6221–9). Key to this work is a solid-phase chemistry approach to synthesise peptide conjugates containing allylic sulfides that, following peptide cyclisation, can be readily copolymerised with N,N-dimethylacrylamide (DMA) controlled by reversible addition−fragmentation chain transfer (RAFT).