This paper presents a detailed overview of techniques to remove organic precursors to disinfection byproducts (DBP) during water treatment. Methods discussed include coagulation and flocculation, activated carbon (both granular and powdered), membranes, and ion exchange. Theory and mechanisms, field observations and operational experiences are discussed. A table compares the advantages and disadvantages of the processes discussed. References are provided so the interested reader can obtain more detailed coverage of specific topics elsewhere. Throughout, the removal of naturally occurring organic materials (NOM) or total organic carbon (TOC) is used as a surrogate for the removal of DBP precursors. Though not as precise, a removal of NOM or TOC is expected to result in precursor removal.