Taurine, or 2-aminoethane sulfonic acid, has long been known to be the major organic product formed from the breakdown of the sulfur-containing amino acids, methionine and cysteine. It is excreted as such in the urine or as bile acid conjugates in the bile. Research over the last 25 years, however, has uncovered an amazing variety of phenomena involving taurine. Despite the fact that the mechanism of action of taurine in some of these phenomena remains to be elucidated, it is clear that taurine is of far more physiological relevance than being the mere metabolic debris of sulfur amino acid...