Oesophageal specimens derived from 70 patients with established invasive squamous cell carcinoma of the oesophagus were histologically reviewed with special reference to the morphological manifestations of human papillomavirus (HPV) infection. Epithelial changes fulfilling the criteria for HPV infection were noted in 23 cases (33%). The presence of HPV antigens was demonstrated by immunohistochemical staining in 7 of these 23 cases. Although acceptable for routine diagnostic purposes, histological typing and immunoperoxidase staining methods are not entirely conclusive of HPV infection. Electron microscopy for detection of viral particles and a molecular hybridization technique have to be used for absolute confirmation and viral subtyping. The results of this pilot study will be used for prospective studies to determine the role of HPV infection in the aetiology of oesophageal carcinoma.