Field experiments have been conducted in Uganda to investigate the use of the insecticides DDT and Benzene Hexachioride for the control of tsetse. Since the Tsetse Research Department of Shinyanga has developed a line of investigation into the possibility of using cattle sprayed with DDT as poison bait for tsetses, it was considered that the alternative method of attack, i.e., treatment of vegetation, should be tried. The preliminarywork has been against Glossina palpalis, R.-D. Results of experiments against this species should provide a basis for work against other species. Experiments have been carried out as far as possible on small islands and headlandson Lake Victoria where the flies exist in isolated communities and where results are nottherefore influenced by infiltration of flies from surrounding bush.