A prospective study was conducted to investigate perinatal mortality rate, stillbirth rate and early neonatal mortality rate in 29 centres throughout Turkey between 1 January 1999 and 31 December 1999. The most frequent causes of mortality were determined according to the modified Wigglesworth classification, and the results were evaluated with respect to the differences between the centres and the regions. The total number of births from all centres was 92 587. Perinatal mortality rate was 34.9 per 1000, stillbirth rate 18 and early neonatal death rate 17.2 per 1000. Perinatal mortality rates were highest with 71.9 and 62.9 per 1000 in the regions that have low socio-economic status and are predominantly rural and semi-urban. The rate was lowest (27.3 per 1000) in the region that is economically more developed. In 23 out of 29 centres, the causes of death were clearly determined. The most important causes of death according to the modified Wigglesworth classification were antepartum stillbirths (42.7%), prematurity (26.0%) and lethal congenital malformations (13.2%). In conclusion, reduction in the perinatal mortality rate in Turkey is likely to be possible only with the co-ordination of the government, universities, obstetricians and neonatologists and improvement of prenatal, delivery and postnatal care and prevention of prematurity. Perinatal mortality studies should be extended and better organised regionally in Turkey.