Photo-responsive polymers have been investigated intensively as important elements for the development of smart materials and devices. Our interest is in polymers functionalized with spiropyran (SP), a well-known photocromic molecule that has the ability to reversibly switch from an uncharged, colorless, benzospiropyran form, to a zwitterionic, planar, highly colored merocyanine (MC) form upon exposure to ultraviolet (UV) or visible light. Controlled radical polymerization (CRP) is a particularly attractive method to produce spiropyran- derivitized polymers as the synthesis of polymers with photochromic units present in defined positions, either along the polymer chain or as the polymer end-group, is readily achievable. This thesis initially documents firstly the synthesis of polymers that possess a single SP terminal unit, produced by atom transfer radical polymerization (ATRP), and their light responsiveness. The second part of this work reports the synthesis and the characterization of a SP derivative with a propyne functional group and the study of its photochromism. The alkyne functionality of the BSP compound was exploited to demonstrate a BSP-based polymeric system that utilizes commercially available polymers, through copper(I) catalyzed azide/alkyne reaction (CuAAC). The third part of this work consists of synthesizing well-defined polymeric systems with complex architectures, such as star or graft copolymer, that bear a high density of SP units in the side chain. The strategy employed consists of combining ATRP and the CuAAC.