Reports on the incidence of renal disease in the avian patient vary,but renal disease is common in poultry and birds of prey. Clinical renal disease is probably under-recognized in the companion bird,with the notable exception of renal tumors in the budgerigar (Melopsittacusundulatus). Diagnosis of renal disease may rely on the identification of consistent clinical signs, clinical pathology, survey radiographs, and laparoscopic evaluation and biopsy of the kidneys. Treatment of avian renal disease relies on supportive care such as fluid therapy and nutritional support. Other treatments vary with the underlying cause and the clinical picture but may include systemic antibiotics, diuretics, parenteral vitamin A, and agents to lower uric acid levels such as allopurinol.