We performed four experiments to examine effects on the mate choices of female Japanese quail, Coturnix coturnix japonica, of observing a male mate with another female. Each experiment was conducted in three phases: (1) a pre-test during which subject females were allowed to choose between two males with which to affiliate; (2) an observation phase, in which subject females either watched or did not watch the male they had spent less time near during the pre-test (their 'non-preferred' male) copulate with a 'model' female; and (3) a post-test when subject females again chose between non-preferred and preferred males. Only females that had watched their non-preferred male mate with a model female during the observation phase spent significantly more time affiliating with him during the post-test than they had during the pre-test. Watching mating did not change females' criteria for choosing males, and non-preferred males that had mated recently were no more attractive to females than were non-preferred males that had not done so, unless subject females actually observed the mating take place. The results were consistent with the hypothesis that female quail copy one another's mate choices. Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.