Renal disease in birds is frequently encountered. Like most other animals, birds are susceptible to a full spectrum of renal insults,such as toxins, tumors, infections, and degenerative conditions. Accurate diagnosis of renal disease is based on a complete history,physical examination, and laboratory evaluation of the patient. Because it is often required for a more definitive diagnosis, special attention is given to histopathologic evaluation of renal tissue,whether through a premortem biopsy or collection at gross necropsy.