Clinical examination of 2192 psittacine birds of both sexes revealed a prevalence of 2.74 per cent (60 birds) of egg-binding. Domesticated species easily bred in captivity were the most commonly affected; the prevalence in cockatiels (15.75 per cent), and in budgerigars (5.73 per cent). An accurate diagnosis was possible in all cases by means of an evaluation of the case history, a visual examination, palpation and radiographic and ultrasonographic examinations. The case history alone was typical in 60 per cent of the cases, and reliable diagnosis was reached with the help of a visual examination in 70 per cent of the cases. Radiographic examination provided a definitive diagnosis in 30 per cent of the cases, especially in those with shelled eggs. Medullary bone proved to be a radio-graphic indication of laminated and thin-shelled eggs. However, laminated and thin-shelled eggs could only be differentiated definitively from abdominal masses, salpingitis and cystic degeneration by means of ultrasonography.