The social organization of the gerenuk in Tsavo East National Park, Kenya, is characterized by single adult male on territories encompassing their entire home ranges, small female-groups of variable composition, often associated with territorial male, and small groups of subadult male. There appear to be no non-territorial adult male ("bachelors"). Subadult male wander about considerably, often alone, before they succeed in taking over a territory. Territorial male perform linked urination/defecation and mark dry twigs with the antorbital gland secretion. Agonistic and courtship behaviour resemble those of other gazelles. Mother-young relations conform to the "hider type" among bovids.