To assess the potential value of Eublemma scitula (Ramb.) as an agent for the biological control of Saissetia oleae (Ol.) on olive and Citrus, studies were carried out, mainly in olive and Citrus groves, in southern France and in Corsica.Observations showed that, in addition to preying on the eggs of S. oleae on olive, Citrus, white heather and myrtle, the larvae of this moth also attacked the other immature stages and pierced the adult female scale to feed on the body contents. Eggs were the preferred food. In addition to S. oleae, the other scale insects attacked were Coccus hesperidum L. and Ceroplastes sinensis Del G. on Citrus, Euphilippia olivina Berl. & Silv. and Pollinia pollini (Costa) on olive, Filippia oleae (Costa) (follicularis Targ.) on Arbutus, Ceroplastes rusci (L.) on fig, Arbutus and myrtle, Eulecanium (Sphaerolecanium) prunastri (Boy.) on plum and apricot, Parthenolecanium carni (Bch.) on grape vines, Kermes vermilio Planch. on oak and Lecanodiaspis sardoa Targ. on Cistus.Three generations a year were observed, and both larvae and pupae overwintered. Eggs were laid close to colonies of scales, preferably those with females that were about to oviposit. The extent to which prey populations were reduced depended on the synchronisation between the development of the predator and its prey. Wide variations were observed between localities in the control afforded.Eublemma scitula was not found attacking colonies of S. oleae tended by Iridomyrmex humilis (Mayr), but the presence of Crematogaster scutellaris (Ol.) did not interfere with predation. On olive, E. scitula was parasitised mainly by Elasmus flabellatus (Boy.), Hockeria bifasciata Wlk. and Apanteles xanthostigmus (Hol.). Two other parasites found attacking the larvae, Copidosoma bolivari Merc. and Cirrospilus subviolaceus Thoms., had not previously been recorded as part of the fauna associated with olive. none