The therapeutic efficacy of numerous anti-cancer drugs is often compromised by premature degradation or insufficient bioavailability during oral or intraven- ous administration. Addressing these limitations, targeted drug delivery to can- cer sites has emerged as a promising approach. This thesis explores the poten- tial of carbon nano-onions (CNOs) as drug carriers, focusing on their synthesis, supramolecular chemistry, chemical functionalisation, and applications in tar- geted drug delivery. The introduction provides a comprehensive overview of CNOs, in the scope of drug-delivery applications. Existing research on CNOs, particularly their non- covalent functionalisation, is discussed and presented in perspective of their po- tential as nanocarriers. A critical analysis of the findings underscores the bene- fits of functionalising CNOs for drug delivery applications, including enhanced aqueous dispersibility, biocompatibility, and drug-loading, all while preserving their inherent physicochemical properties. Research presented in this thesis encompasses the targeted delivery of gemcit- abine to CD44 receptor-overexpressing pancreatic cancer cells using hyaluronic acid-functionalised CNOs, and the use of CNOs as nanocarriers for targeted de- livery of doxorubicin to folate receptor overexpressing cancer cells. These stud- ies demonstrate the potential of CNOs as versatile platforms for targeted drug delivery, with the ability to be tailored for specific cancer types and treatment strategies. The thesis emphasises the promise of CNOs for advancing cancer therapies. The demonstration of CNOs as effective and non-toxic drug carriers for targeted can- cer therapy serves as a valuable foundation for further exploration and optim- isation of carbon nanoparticle (CNP)-based nanocarriers, ultimately pushing the boundaries of drug delivery systems and improving patient outcomes. Challenges associated with the use of CNPs as nanocarriers are also discussed, outlining the scope for further investigation.