The lesser kestrel (Falco naumanni) is considered a socially monogamous species in which extra-pair copulation occurs at a low rate. A wide study of extra-pair mating behaviour carried out on this species found that mated females do not solicit extra-pair copulation and reject all copulation attempts elicited by extra-pair males. In fact, the infrequent instances of extra-pair fertilization found were attributed either to re-mating after divorce, or polygyny. Here I describe an observation indicating that females also promote and accept promiscuous mating, attaining and consummating extra-pair copulation. I suggest the possibility that promiscuous behaviour could vary among different populations in this species, as it has not yet been reported, in spite of the extensive work performed in this respect.