PIP: A history of colonial exploitation and a development model that concentrates wealth and excludes a large proportion of the population from the development process are the principal determinants of income distribution in Colombia. This work analyzes the extent of malnutrition among the poorest 30% of the Colombian population. The National Plan for Feeding and Nutrition (PAN), an important component of the national development plan, strives to improve the nutritional status of the most vulnerable population groups living in rural areas and marginal urban neighborhoods, with particular emphasis on mothers and children. The program initially was focussed on 11 priority regions where 5 types of interventions were developed: primary health care, environmental sanitation, food production, food distribution, and nutrition education. Because of the good results initially obtained, PAN now covers the entire national territory. A 1977 survey stratified by socioeconomic levels indicated that among the poorest 30% of the population, 67% of the children examined had low weight for age caused by a combination of chronic and acute malnutrition. 12% were considered to have severe and 23% moderate malnutrition. 8% had severe and 17% had moderate problems of height for age. 26% had deficient weight for height. Comparison of the data to normal values published by the World Health Organization clearly demonstrates the pattern of overall malnutrition indicated by weight for age figures. It can be concluded at 33% of children in the poorest 30% of the population are normal, 31% have mild malnutrition, 23% moderate malnutrition, and 12% severe malnutrition. Data on height for age indicated that 43% were normal, 32% had mild chronic malnutrition, 17% had moderate chronic malnutrition, and 8% had severe chronic malnutrition. The prevalence of acute malnutrition in the poor population measured by the ratio of weight to height was less than that of chronic or overall malnutrition. 21% were considered to show mild, 4% moderate, and 1% severe acute malnutrition. Nutritional status was greatly influenced by age, with the lowest rates of malnutrition occurring in children under 1. Mortality among children aged 1-2 years probably was responsible for a decline in malnutrition rates in children over 2. Patterns of malnutrition in children of the poorest 30% of the Colombian population were quite similar in the 11 departments included in the 1977 survey. Comparison with earlier data indicates that the nutritional status of children in the poorest population sector has not improved since the 1960s.