To establish incidence and prevalence of children needing palliative care in Wales. Children were identified in three ways: (1) from paediatricians using the Welsh Paediatric Surveillance Unit (WPSU); (2) referrals to the specialist palliative medicine service based in Cardiff; and (3) children under the care of the two principal children's hospices serving Wales. All children referred or reported between January 2001 and December 2002 were included. A total of 226 children were identified. Fifty (22%) were identified by paediatricians, 58 (26%) were referred to the specialist paediatric palliative medicine service, 158 (70%) had been under the care of a children's hospice, and 34 (15%) were identified by more than one source. This study identified approximately 3.75 per 10000 children. This is about half the prevalence figures quoted in the ACT/ RCPCH document in 1997. The study may underestimate prevalence. Children needing palliative medicine are still under-recognized in Wales. The overlap between children's hospice care and specialist paediatric palliative medicine is relatively small.