Natural organic matter (NOM) generally influences water treatment processes such as coagulation, oxidation, adsorption, and membrane filtration. NOM contributes colour, taste and odour in drinking water, fouls membranes, serves as a precursor for disinfection by-products, increases the exhaustion and usage rate of activated carbon and may promote microbial growth in water distribution networks. High performance size exclusion chromatography and fluorescence excitation-emission matrices were used to characterize NOM relatively quickly and with minimal sample preparation. These and other tools were used to improve our understanding of NOM character and behaviour during drinking water treatment. The study demonstrates the potential of multiple NOM characterization tools for the selection, operation and monitoring of water treatment processes.