Analysis of Herbicides, insecticides and pesticides occupy a sizable volume of analytical services and research followed by fungicides and rodenticides. There is regular update of the chemistry of these compounds; chlorinated pesticides are mostly replaced by less toxic organophosphorous derivatives and natural pesticides replacing synthetic ones. We adapt both EPA and main stream published methods using GC/MS for their analysis. We also develop and validate domestic HPLC and GC/MS/MS methods as needed to solve analytical problems.