Seventy-nine participating laboratories were instructed to dilute the provided concentrated water sample to a specified volume and analyze for nine specified metals. In their analyses for cadmium, lead, silver, and zinc, participants were instructed to use new methods to appear in the 12th edition of 'Standard Methods for the Examination of Water and Wastewater', which were provided with the sample. The desirability of the various chemical methods are compared and discussed. The few participants using atomic absorption spectroscopy achieved excellent results for all metals except aluminum, which was not measured by this method. Use of the spectrograph produced good results for zinc and cadmium, but appeared less satisfactory for the analysis of aluminum, silver, chromium, lead, copper, iron, and manganese.