Responsive polymeric assemblies and hybrid superstructures fabricated from stimuli-sensitive polymers and inorganic nanoparticles (NPs) have been the subject of extensive investigations during the past few decades due to their distinct advantages such as an improved water solubility, stimuli-responsiveness, excellent biocompatibility, and facile introduction of functional units. In addition, the chemical compositions of polymeric assemblies and corresponding hybrid superstructures can be modulated via the initial synthetic design to target desired functions, fabricate smart nanostructures, and explore morphology-dependent functional optimization. Promising applications in the field of imaging, sensing, drug/gene delivery, diagnostics, and nanoreactors are being extensively investigated. This perspective article focuses on recent developments, microstructural control, and biomedical applications of stimuli-responsive polymeric assemblies as well as responsive hybrid superstructures fabricated from responsive polymers and inorganic NP building blocks (gold NPs and magnetic iron oxide NPs), and highlights their current status and future developments with selected literature reports.