The data collected by the Bandafassi demographic study in Eastern Senegal, a small-scale intensive and experimental follow-up survey on a population of about 7,000 inhabitants in 1983, were analyzed to derive an estimation of the life table. The use of the multi-round survey technique, combined with anthropological methods to estimate the ages or collect genealogies, results in unusually reliable data. Taking into account the uncertainty of the estimates related to the small size of the population, the measures of mortality show a high mortality level, with life-expectancy at birth close to 31 years; a pattern of infant and child mortality close to what has been observed in other rural areas of Senegal; a seasonal pattern in child mortality with two high risk periods, the rainy season and the end of the dry season; an adult mortality pattern similar to what is described in model life tables for developed countries; no significant differences according to sex or ethnic group. The example of the Bandafassi population study and of a few similar studies, suggests that one possible way to improve demographic estimates in countries where vital registration systems are defective would be to set up a sample of population laboratories where intensive methods of data collection would continue for extended periods.