SUMMARYBalda, R. P. and J. L. Brown. 1977. Observations on the behaviour of Hall's Babbler. Emu 77: 111–114. Hall's BabblersPomatostomus halliwere studied for seven days in southern Queensland. Eight flocks ranged in size from five to fifteen birds. Flocks maintained exclusive home ranges that varied from 1.8 to 3.5 hectares. Each home range contained from four to eleven nests. Babblers roosted communally and constantly foraged as a flock. One nest with two eggs was discovered and observed. The female always signalled by postures and vocalizations when she left the nest and entered the flock. Flock members were seen preening and feeding the female. Our few data suggest that large flocks may initiate breeding earlier in the season than small flocks. At this time it may take more auxiliary helpers to raise a brood than later in the season when conditions are more hospitable. Few aggressive encounters were observed and numerous types of co-operative behaviour were seen.