This review is focused on the chemical design and synthesis of polymer-based drug delivery systems, in particular with stimuli-responsive nanoplatforms for cancer treatment. We provide a brief description of the properties, synthesis and advantages of amphiphilic block copolymers, including polyether-polyester and polyether-polyanhydride. As for stimuli-responsive polymers, we detail the recent innovative techniques for constructing smarter, more precise and optimally tuned nanocarriers that release drug in the disease site. This review is presented in the context of polymer science research, with special attention focused on the tailor-made polymers containing specific chemical functionalities. (C) 2016 Wiley Periodicals, Inc.