This dissertation describes the development of a new method for the synthesis of nanostructured branched polymers through the combination of two techniques, atom transfer radical polymerization and microemulsion polymerization. The importance of these materials, current challenges associated with their synthesis and details of our proposed methodologies are highlighted in Chapter 1. Chapter 2 describes an in-depth and systematic investigation into the self-condensing vinyl polymerization of AB* inimer in microemulsion for the synthesis of hyperbranched polymers with controlled structures. The following chapter examines the discovery of a competing initiation process that occurs during the atom transfer radical polymerization initiated by activators generated by electron transfer in microemulsion. In Chapter 4, the effect of branching point structures and densities was studied between azido-containing hyperbranched polymers and cross-linked nanogels on their loading efficiency of alkyne-containing dendron molecules. These results represented the first comparison between hyperbranched polymers and cross-linked nanogels to explore the effect of branching structures on their loading efficiencies. Chapter 5 extended this study to branched core star polymers with similar sizes and molecular weights but different branching structures, X versus T linkages and tested them on their loading efficiencies with alkyne-functionalized dispersed red dye.