The VIIIth International Congress of the International Prirnatological Society was held from 7 through 11 July 1980 in Florence, Italy, under the auspices of the host institution, the Istituto di Antropologia of the University of Flor~nce. More than 300 papers and abstracts were presented either at the main Congress or in 14 pre-Congress symposia the week earlier (so scheduled to avoid conflicting with either the main invited lectures or the contributed paper sessions). This volume consists of the contributed papers concerning primate behavior, with special emphasis on those social aspects that reflect on or affect primate biology. Clearly, this is one of the more important and popular subdisciplines in primatology today. We have thus restricted the subject, in agreement with the publishers, in order to ensure a successful and useful volume that is likely to be generally noticed and widely available, as these up-to-date contributions deserve. Furthermore, we have compiled this volume in a fairly new way for congress proceedings. In view of space limitations, and the need to guarantee a high-quality and sufficiently specialized book, we subjected all manuscripts to a four-level internal review process and selected only the best 23 of the 50 submissions. We favored natural-observation work over captive studies. This rejection rate of 54% exceeds that of almost all reviewed scholarly journals.