 The infant mortality rate IMR in Tamil Nadu as a whole is approximately 601000 live births. The population selected for inclusion in this study is poorer economically and has worse health status than the average for Tamil Nadu. It is likely, therefore, that the infant mortality rate in this area is higher than the state as a whole. We have estimated it at 701000 live births. The study design for this project calls for vital status assessment to conclude at 6 months of age. Therefore the expected mortality rate in the first six months will be lower than the total IMR. Mortality rates decline dramatically with age, even in the first year of life. Reasonable estimates are that 75 of total infant mortality occurs in the first six months of life. Applying this figure to the estimated IMR of 701000 live births gives a 6-month infant mortality rate IMR-6 of 52.51000 live births. 