Incidence rates of cancers of childhood in Thailand are presented for the first time, and compared with results from cancer registries in Asia, Europe and the USA. As elsewhere in the world, leukaemia (principally acute lymphocytic), brain tumours and lymphomas comprise two-thirds of all childhood neoplasms. Carcinomas are rare, but the principal sites (liver, nasopharynx, thyroid and salivary gland) are extremely unusual elsewhere. Several features of the cancer pattern correspond to that in other Asian populations (China, Japan, Philippines), in particular the low incidence of Hodgkin's disease, Wilms' tumour and Ewing's sarcoma. Conversely, Burkitt's lymphoma is more common than elsewhere, although this may represent increasing awareness of this diagnosis amongst clinicians in recent years.