An issue of concern to both utilities and the public is that of metals in drinking water. The Lead and Copper Rule, which is currently being reassessed, was designed to limit the amounts of these metals in drinking water. An important question being asked by consumers and the water industry is: can consumers be sentinels of water quality and detect problems at or below regulatory or guideline levels? This study examined this question in terms of copper corrosion and the taste of copper in drinking water. The study investigated both copper chemistry and taste. Thirty-six healthy volunteers participated in taste testing for copper at ten concentrations from 0.1 to 8 mg/L. The results indicate that about 75% of the consumers tested could taste copper below the aesthetic based SMCL of 1 mg/L, but the other 25% could not and some consumers could not even taste copper at 8 mg/L which was the highest concentration tested. Thus, some consumers could be effective sentinels for detecting copper in their tap water, while others cannot. Includes 12 references, figure.