Despite many early accomplishments in nanomaterial design and synthesis, there remains a significant requirement for novel inorganic and organic nanohybrids with the potential to act as efficacious molecular imaging agents and theranostic vectors. The functionalization of surfactant-coated inorganic nanoparticles with polymer shells represents one of the most suitable and popular methods to synthesize polymer/inorganic nanohybrids for theranostic applications. Key requirements for effective imaging agent design include water dispersibility, biocompatibility and functionality to enable enhanced contrast magnetic resonance imaging (MRI), positron-emission tomography (PET), computed tomography (CT), or ultrasound modalities. In this Perspective, we highlight recent advances in the fabrication of organic/inorganic nanohybrids exploiting functionalized polymers prepared using reversible addition-fragmentation chain transfer (RAFT) polymerization. The polymer shells can imbue favorable traits to the nanoparticles such as stealth, image enhancement, storage (and release) of therapeutics, and sensitivity to biological stimuli. In this Perspective, we discuss the design and synthesis of hybrid nanoparticles and discuss current trends and future opportunities.