Laboratory space fumigations were made to determine the effectiveness of six candidate fumigants against adults of the confused flour beetle, Tribolium confusum Jacquelin duVal, and the cigarette beetle, Lasidoerma serricorne (F.), and against the larvae of the black carpet beetle, Attagenus megatoma (F.). At the LD⁹⁵ level, the toxicity of V-/C 3-668 (O-methyl S, S-dipropyl phosphorotrithioate) and hydrazoic acid (HN³, was greater than the toxicity of methyl bromide to all three insect species. Stauffer R-8963 (O, O-diethyl S-(3,4,4-trifluoro-3-butenyl) phosphorothiate) were more toxic than methyl bromide to cigarette beetles and to black carpet beetles at the LD⁵⁰ level. Stauffer R-8963 was much more effective than methyl bromide against confused flour beetles at the low dosages but slightly less effective than methyl bromide at the higher dosages, GC-9245 (1,1,2, 3-pentachloro-1,3,-trifluoropropane) was more toxic than methyl bromide to cigarette beetles, and GC-8163 (1,2,2,3-tetrachloro-1,1,3, 3-tetrafluoropropane) was less toxic than methyl bromide to all three species.