Leaf volatiles repel mosquitoes. Female Aedes aegypti and Anopheles arabiensis (N = 9) landing behaviour was tested in response to volatile extracts from five plants traditionally used to repel mosquitoes. Volatile extracts have been taken from burning, fresh, and dried leaves. N,N-Diethyl-meta-toluamide (DEET, 10%) was used as a control to indicate maximal repellent response. Extracts were added to a hand-rubbed, heated membrane and compared to a hand-rubbed, heated membrane alone in a two-choice assay. Significance is determined by two-way analysis of variance (ANOVA) with Dunnett's simultaneous post hoc test at P < 0.05 unless otherwise indicated (** P < 0.01; *** P < 0.001). Error bars represent the standard error of the mean (SEM).