This is a review of mustelid spacing patterns. The Mustelinae appear to have intrasexual territories where ♂♂ are territorial against ♂♂, ♀♀ against ♀♀, but there is extensive territory overlap between sexes. Mustelids of other subfamilies appear to have variations on this theme; usually female territories are replaced by territories of family groups of one adult ♀ and her most recent offspring. Sea otters and European badgers do not appear to fit into these organizational schemes.
There is a strong correlation between degree of intrasexual territoriality, sexual dimorphism in body size, degree of body elongation and degree of carnivory. It is suggested that energy requirements of individuals may tie these correlations together.