The presence of human papillomavirus (HPV) genomes 6, 11, 16 and 33 in 16 patients with laryngopharyngeal carcinomas was examined by means of a polymerase chain reaction. HPV genomes were detected in 75 per cent of cases. In hypopharyngeal carcinoma, HPV 6 and 11 were present in adjacent tissue but absent from the tumour. HPV 16 and 33 were present in 40 per cent of laryngeal tumours and adjacent tissue. These results suggest that HPV 16 and 33 may be closely associated with the development of some laryngopharyngeal carcinomas.