Seyfarth (1977, Journal of Theoretical Biology, 65, 671-698) proposed a mod
el of social grooming among female monkeys that has had an enormous influen
ce in the primatological literature. To test this model, I reviewed publish
ed data on primate grooming behaviour, using meta-analytical techniques. An
analysis of grooming behaviour in 27 different social groups belonging to
14 different species revealed that a significant role in the distribution o
f grooming was played by attraction to high-ranking animals, attraction to
kin and competition for grooming partners. These results confirm the majori
ty of the predictions of the model. The need for more observational data on
grooming (and other affiliative interactions) in New World monkeys, and ex
perimental data on the relations between the exchange of grooming and the f
ormation of agonistic alliances, is emphasized., (C) 2001 The Association f
or the Study of Animal Behaviour.