Chacmas usually live in social groups composed of multiple adult males, adult females, and their offspring. Occasionally, however, very small groups form that include only a single adult male and several adult females. Chacma troops are characterized by a dominance hierarchy. Female ranking within the troop is inherited through the mother and remains quite fixed, while male ranking is often in flux, especially when the dominant male is . Chacmas are unusual among baboons in that neither males nor females form strong relationships with members of the same sex. Instead, the strongest social bonds are often between unrelated adult males and females. Infanticide is also common compared to other baboons species, as newly dominant males will often attempt to kill young baboons sired by the previously dominant male. Baboon troops possess a complex group behavior and communicate by means of body attitudes, facial expressions, vocalisations and touch.
