INTRODUCTION N-methylcarbamates and N-methylcarbamoylox-imes are among the most widely used pesticides in the world. U.S. EPA method 531.2 provides guidelines for monitoring these compounds in ground and surface waters as well as drinking water. Reversed-Phase High Performance Liquid Chromatography (RP-HPLC) is the preferred method for separating carbamates. Most alternate methods for analysis have signifcant limita-tions. Gas chromatographic analysis has proven unsuc-cessful due to degradation of the analyte compounds during vaporization. HPLC with UV detection does not offer the sensitivity or specifcity required for the sampl matrices of interest. HPLC with positive mode electro-spray ionization mass spectrometry has been shown to be a promising alternative, but it increases the expense and expertise required for the analysis. Postcolumn derivatization with fuorescence detec- tion after a reversed-phase HPLC separation is consistent with U.S. EPA Method 531.2. This method delivers highly sensitive determinations of carbamate compounds.