The objective of this study was to describe the complex chemistry of the formation of chloro- and bromophenols during the chlorination of bromide- and phenol-containing waters in order to define conditions that promote the formation of critical products (2-bromophenol and 2,6-dibromophenol) under realistic drinking water treatment conditions. Experimental approach is based on: a critical evaluation and compilation of existing second-order rate constants for HOX-phenol reactions; determination of unknown second-order rate constants for reactions of HOCl and HOBr with phenolic compounds over a wide pH range; quantification of product distribution of the formed halophenols; and, formulation of a kinetic model. This kinetic model enables us to investigate the influence of some water quality parameters such as the concentration of phenol, ammonia, bromide and the pH on the product distribution. Includes 7 references, table, figures.