In this project, we report the synthesis of well-defined charged polymers with narrow molecular weight distribution using Reversible Addition Fragmentation chain Transfer (RAFT) polymerisation. Block-copolymers were obtained by sequential RAFT polymerisation. Optimal control in RAFT polymerisation was confirmed by the linear increase of molecular weight and the low PDI of the polymers (<1.2), as determined by ¹H NMR analysis and GPC, respectively. Spherical sub-100 nm nanoparticles were formed by self-assembly of oppositely charged polyelectrolytes, poly(methacrylic acid) (PMAA) and poly(2-(dimethylamino) ethyl methacrylate) (PDMAEMA) with poly(ethylene glycol) methyl ether methacrylate (PEGMA) acting as a stabilising agent. The encapsulation of hydrophilic and hydrophobic anticancer drugs into the nanoparticle formulations and their release profiles at different pH environments are currently being evaluated.