The gross and histological appearances of the lesions of tuberculosis in 36 wild badgers found to be infected with Mycobacterium bovis are described. These badgers were examined over a period of two years during an investigation into the possible epidemiological association of tuberculosis in badgers and cattle. The possible significance of the lesions in transmission of M bovis to cattle and other badgers is discussed. The histological appearance of the lesions was considered to be indicative of a lesser hypersensitivity reaction than is seen in the bovine.