IN the course of investigations on s-triazines, we have discovered a new synthesis of 2-alkoxy- and 2-alkylthio-4,6-dichloro-s-triazines. These substances can be obtained by the reaction of an alcohol or a thiol with cyanuric chloride and 2,6 x collidine as the acid acceptor. The yield was approximately 80–90 per cent. In a further systematic investigation, we found that in these compounds the chlorine atom can be specifically substituted in good yield by an alkylamino, alkyloxy or alkylthio group.