Efficient and targeted delivery of nucleic acids is critical for realizing their full therapeutic potential. Nucleic acids as therapeutic agents suffer from instability, inefficient biodistribution and are susceptible to degradation, limiting their clinical efficacy1. Emerging polymer delivery platforms offer innovative solutions capable of protecting therapeutic agents, overcoming biological barriers, and guiding biological interactions through highly tuneable properties and engineered architectures2. However, polymers used in existing delivery systems are based on chemistries that generate dispersity, leading to variations in molecular weight, uncontrolled branching or monomer sequencing, making comparisons between polymers more challenging, and limiting progress in the nucleic acid delivery field3. A highly controlled, sequence-specific polymer platform could help uncover what key architectural parameters are critical for improving delivery outcomes. Peptides are sequence specific biopolymers that can be synthesised with excellent control. Incorporating peptides into an existing polymer delivery system could allow for even greater control over polymer: composition, branching, molecular weight, and chemical functionality. Here we use solution peptide synthesis to prepare dendronised amphiphilic peptide oligomers (DAPOs). DAPO’s are based on oligomers of amino acids and incorporate highly branched poly(amidoamine) (PAMAM) dendrons to facilitate effective delivery of nucleic acids in vitro4,5. I will show how we have precisely tuned the hydrophobicity and the density/size of PAMAM groups within a unimolecular polymer, by controlling the exact number and generation of dendrons, and the incorporation of various tail lengths of fatty acids, creating a fully modular system. The DAPO system presents the basis of a modular approach to unimolecular dendronised polymer synthesis. This will subsequently enable a more systematic approach to developing a clear understanding on how polymer structures aid or obstruct nucleic acid delivery in general. Thereby providing insights that guide the development of next-generation non-viral polymer-based delivery vectors and the continued development of tailored therapeutics like gene therapy.