For more than 20 years, researchers have been using resinbased separation methods to isolate natural organic matter (NOM) for the purposes of assessing disinfection byproduct (DBP) precursors. Most have employed non-standard precursor methodologies, which makes comparison between studies very difficult. As new data of this type are acquired, it is important to be able to place them into context of the existing database. In this study, we critically reviewed and summarized this vast collection of literature data. Using some of the well-tested precursor models, we were able to normalize the data allowing cross comparison between studies using differing precursor testing regimes. These comparisons revealed some distinct differences between hydrophobic, hydrophilic and transphilic NOM. In addition, some of these distinctions are general, being evident across the various DBP classes (e.g,. trihalomethanes, di & trihaloacetic acids).