Samples of up to ten study skins for each of five species ofMicrohierax, two species ofPolihierax, one species ofSpiziapteryxand 23 species of smallFalcowere measured for 24 dimensions of the head, wings, tail and feet. The logarithmic (log10) valucs of the means of each mcasurcmcnt for each species, and for each sex where dimorphic, were compared using cluster and factor analyses.Microhieruxfalconets are most similar to the African Pygmy FalconPolihierax sernitorquatusbut are morphometrically distinct from all other falconets and smallFalcospecies. The five species of Microhierax falconets are morphometrically similar, sexually dimorphic and probably replace one another ecologically, since all are allopatric or differ in proportions and habitat where parapatric (two species). Prelim[nary observatioris on the hunting behaviour and social organization of the Rlack‐thighed FalconetMicrohierux fringillariusindicate that the genus has morphological and social specializations for aerial capture of large forest insect