Taurine is abundantly present in phagocytic cells and provides protection against cytotoxicity caused by reactive oxygen species (ROS). The reaction between taurine and HOCl, a toxic product of the myeloperoxidase (MPO) system, generates a more stable and less toxic product, taurine chloramine (TauCl). TauCl has also been shown to inhibit the production of superoxide anion (O2-) and nitric oxide (NO). In this review, we compare the effect of taurine and TauCl on the production of these reactive species in phagocytes. First, TauCl inhibit PMA-derived O2- production and this is associated with inhibition of p47phox phosphorylation and of p47phox and p67phox translocation. Second, TauCl inhibits LPS-induced iNOS expression and NO production. This occurs by direct inhibition of Ras activation, ERK1/2 phosphorylation and NF-kappaB activation. Third, TauCl by itself increases the expression of heme oxygenase-1 (HO-1) and enhances HO activity. Carbon monoxide (CO), a product of HO activity, is able to inhibit both O2- and NO production. Combined, these effects of TauCl appear to provide cytoprotection against the inadvertent cytotoxicity caused by overproduction of O2- and NO.