Modular segmented hyperbranched polymers, amenable to facile post-polymerization functionalization, were created via two distinct approaches. Self-condensing vinyl polymerization via reversible addition–fragmentation chain transfer (RAFT) polymerization and RAFT polymerization with a divinyl comonomer were employed to create well-defined highly branched materials containing activated esters amenable to highly efficient functionalization in a modular manner.