The Great Indian Bustard Ardeotis nigriceps, a large ground-dwelling bird of India and Pakistan, is declining throughout its entire range. Little has been published in detail on the behaviour of this species. This work presents an ethogram of the species describing 63 individual behaviours grouped under 11 broad categories: alert, resting, comfort and maintenance, locomotion, ingestive and excretory, antagonistic, interspecific response, sexual, maternal, vocalizations, and reflexes. National and site-specific recovery action plans for Great Indian Bustard are in process and ex situ conservation is one of the proposed measures. A better understanding of Great Indian Bustard behaviour is essential for both ex situ and in situ conservation. Precise descriptions of behaviours presented here provide a standard that can be used for systematic and quantitative study of behaviours of the species and which could be of significance in ex situ breeding.