UV/H2O2 advanced oxidation of drinking water for taste and odour control was performed using natural waters to optimize treatment conditions and monitor effects on chlorine decay, chloramine decay, and disinfection by-product (DBP) formation. The optimal dose of H2O2 for the removal of two taste and odour compounds in a raw water sample was 6-10 mg/L. From bench-scale tests, both UV alone (2000 mJ/cm2) and UV/H2O2 resulted in lower levels of chlorine and chloramine residuals when compared to controls. The application of UV/H 2O2 to natural water samples resulted in variable (water-specific) effects on DBPs, with considerable differences between concentrations in controls and in samples exposed to UV/H2O2.Results from this research highlight the importance of performing site-specific evaluations when establishing the feasibility of using UV/H2O 2 for taste and odour control, since it may have a significant impact on secondary disinfectant stability and DBP formation in the distribution system in some waters.