Over the past several years, degradation products of acetanilide/acetamide herbicides: ethanesulfonic acid (ESA) and oxanilic acid (OA), have been found in U.S. ground waters and surface waters.  The substitution of the sulfonic acid or the carbonic acid for the chlorine atom greatly increases the water solubility of degradates relative to the parent compound and contributes to the increased potential for leaching into groundwater.  As a result, alachlor ESA and other acetanilide degradation products were listed on the 1998 Safe Drinking Water Act Contaminant Candidate List (CCL). One acetamide and five acetanilide herbicides are currently registered for agricultural use in the U.S.  The next step in the CCL-process is to collect data on the concentrations and occurrences of these compounds in the nation's drinking water supplies.  However, the existing analytical methods for measuring chloroacetanilide degradates do not address issues specific to analyzing these compounds in drinking water.  Because many of the methods were developed for ground water, dechlorination was not addressed nor was the method tested in all types of drinking water matrices.  In addition, existing methods do not address all twelve ESA and OA degradates of the six U.S. registered acetanilide/acetamide herbicides.  The focus of this research was to develop a sensitive and specific analytical method for the analysis of alachlor ESA and other chloroacetanilide degradates in drinking water.