Anaemia of inflammatory disease is a common cause of anaemia in routine veterinary practice. It is most often mild to moderate, normocytic, normochromic and non-regenerative. Shortened red cell life span, inhibition of iron metabolism and impaired bone marrow response to erythropoietin all contribute to its development. Although anaemia of inflammatory disease is a well-known cause of anaemia in dogs and cats, there is a lack of epidemiological information because specific diagnostic criteria have not been established in veterinary species. Anaemia of inflammatory disease is associated with a poor outcome in various disease states in human medicine; however, its clinical significance and treatment in veterinary medicine are not well understood. This review article describes anaemia of inflammatory disease in dogs and cats and considers its potential significance.