Nanotechnology has greatly advanced in the past decade and provides immense potential for the development of improved therapeutic and diagnostic tools for the treatment, prevention and diagnosis of various diseases of the central nervous system, cardiovascular system and cancer. Due to their small size in dimension, it is believed that nanoparticles are able to interact with cells at the molecular level more efficiently and provide better targeting ability towards desired cells and tissues with greater precision and efficacy. Nano-based delivery systems using polymers (e.g. polymeric micelles and polymer-drug conjugates) and lipids (e.g. liposomes, and solid lipid nanoparticles can help: i) increase solubility; ii) improve tumour targeting; (iii) decrease toxicity; (iv) overcome drug resistance, and v) prolong circulation half-life by modifying the surfaces of these nanoparticulate drug delivery systems and increasing drug payload to the target cells. The complexity of nanomedicines requires a holistic assessment of the quality, safety and efficacy of the product. This talk will focus on the challenges of developing these advanced drug delivery systems to match with the current regulatory expectation.