Most carnivore species are solitary and tend not to associate either with members of the same sex or with the opposite sex. In contrast, coati adult females and juveniles live in stable groups, called 'bands'. Coatis display complex cooperative behaviours, and their bands resemble primate female-bonded societies in various features. In this study we examined spatial association patterns among zoo-living ring-tailed coatis and related it to the patterns of affiliative and aggressive interactions. We found that coati females did not associate or interact with one another randomly. A cluster analysis on spatial association data revealed two main subunits, the size and composition of which were the same in two observation periods. Furthermore, the distribution of affiliative and aggressive interactions of the coatis reflected patterns of spatial association. Affiliative behaviour was more frequent between members of the same subunit than between members of different subunits, whereas aggressive interactions were more frequent between subunits than within subunits. We discuss the implications of these findings for coati social organisation suggesting that the two subunits may reflect the potential for subgroup formation and fission-fusion dynamics in wild populations.