A large and long-legged hawk, this species has a long narrow tail and relatively short rounded wings, which allow it to move easily in the interior of forests. On adults the head has a black crown, white eyebrow streak and eyes are red. Adults typically have blue-grey dorsal plumage with grey barring on the chest and belly. Both sexes are similar, though as with other raptors the females are larger. Juveniles are very similar to the juveniles of other Accipiter species, with brown dorsal plumage and a dirty-white, heavily streaked belly and yellow eyes which change colour as the bird matures. The laingi subspecies is smaller and somewhat darker than the typical mainland (atricapillus) form. While island and mainland populations may overlap along some areas of the Coast Region, A.g. laingi is considered genetically distinct. Information about subspecies biology is derived from the species as a whole.