In a prospective study of 257 children in Lusaka during their first year of life the infant mortality rate was 118 per thousand live births. Deaths were due to prematurity and respiratory problems during the first few months of life, and diarrhoea, measles, and malnutrition during the later months. The low birth weight rate was 11 per cent. Growth was good during the first 6 months, but thereafter there was faltering in weight gain and gain in length faltered after 8 months. By age year 1 only 12 per cent attained the average weight-for-age and 8 per cent the average height-for-age. Breast feeding decreased in frequency very gradually over the first year with 66 per cent of children still being breast-fed more than six times a day at a year. Meals were usually given only three times a day and consisted mainly of maize porridge with vegetables, beans, or meat when it could be afforded. Over 70 per cent of children were fully immunized. Milestones were generally achieved at expected ages or even earlier. Where they were delayed most of the children affected died within a couple of months. Recommendations are made on the surveillance of infants in urban areas and the provision of a precooked fortified appropriate weaning food obtained at Health Centres.