It has been about 10 years since the first intentional preparation of hyperbranched polymer was disclosed. Hyperbranched polymers, as well as dendrimers, may fmd utilities in the areas where the structural uniqueness of these polymers gives merit. There has been much progress in the structural understanding and the methods of synthesis of these polymers. However, functional understanding and utility of these polymers are still in infancy. Better understanding on physical properties of these polymers, such as solubility and miscibility of these polymers in solvents or with polymers, and functional group dependency to the thermal relaxation process are needed for further development of the subject.