The population of Malaysia is approximately 14 million and theoretically 1 in 2500 marriages are between heterozygotes for thalassaemia and 1 in 10,000 children can be expected to have thalassaemia major. Hypertransfusion is not possible because of insufficient blood supplies and each child requires an iron chelator, Desferal, at US$5800 a year for life: this high cost makes it sizeable proportion of the 'active reproductive' population. Abortion is not legal and antenatal diagnosis has not bee established. An approach to the prevention of this disease would be public education and identification of carriers. Numerous techniques have been utilised in population screening for traits of thalassaemia and haemoglobinopathy. These include osmotic fragility tests; blood smear examination for basophilia, microcytosis, and hypochromia; and genetic studies. Blood smear examinations are extremely subjective and interpretations depend upon the skills of a trained technologist. Osmotic fragility tests although cheap are cumbersome and require accurate preparations of saline solutions. Genetic studies are not available in the region. The medical examination for entrance to colleges and institutions includes investigative procedures such as chest x-ray and urine examinations. In addition a blood sample could be analysed for the red cell parameters. A similar study could be attempted for all secondary school leavers. The current estimated cost on the Coulter S as in this study was 80 cents (U.S.) in contrast to the prohibitive costs of managing a case of transfusion-dependent thalassaemia. These two groups would cover a sizeable proportion of the 'active reproductive' population. Analysis of the red cell parameters provides useful information for the identification of carriers of alpha-, beta-, delta-beta-thalassaemia and HbE. Additional studies which include haemoglobin analysis and serum ferritin would provide the necessary evidence for the confirmation of these findings.