Case 80866 -51- ABSTRACT With the present invention it has now been found that certain 4-(trifluoromethyl)pyridine compounds and active compound compositions comprising such compounds are suitable for controlling nuisance, disease carrying or haematophagous (blood feeding) insects pests incl. dipteran, 5 triatominae and cimicidae insect pests by knockdown or by or blood feed inhibition. In one embodiment, dipteran pests are selected from flies and mosquitoes, including insecticide-resistant flies and mosquitoes, as well as fly and mosquito vectors of pathogenic disease. Target cimicidae insect pests are selected from bed bugs. Target triatominae pests are selected from kissing bugs Other aspects of the present invention will also be apparent in the detailed description which 10 follows.