The Pomatostomidae are small to medium-sized birds endemic to Australia-New Guinea. For many years, the Australo-Papuan babblers were classified, rather uncertainly, with the Old World babblers (Timaliidae), on the grounds of similar appearance and habits. More recent research, however, indicates that they are too basal to belong the Passerida – let alone the Sylvioidea where the Old World babblers are placed – and they are now classed as a separate family close to the Orthonychidae (logrunners). Five species in two genus are currently recognised, although the red-breasted subspecies rubeculus of the grey-crowned babbler may prove to be a separate species.

The Old World babblers or Timaliidae are a family of mostly Old World passerine birds. They are rather diverse in size and coloration, but are characterised by soft fluffy plumage. These are birds of tropical areas, with the greatest variety in Southeast Asia and the Indian subcontinent. The timaliids are one of two unrelated groups of birds known as babblers, the other being the Australasian babblers of the family Pomatostomidae.