In 1998, the Kenyan DemographicandHealthSurvey (KDHS) estimated that 33% of Kenyan children were stunted, one-third of which were severely stunted. During a one-month study period, in the summer of 2000, 161 children age twenty-three months and younger were seen at clinics in the Mathare Valley, Nairobi, Kenya. Height and weight were measured on all children; z-scores were calculated from the anthropometrical measurements. A z-test was used to compare the height-for-age of children twenty-three months of age and younger living in the Mathare Valley to the 1998 KDHS statistics. The results demonstrate that there was a significant increase (p < 0.01) in the prevalence of stunting of children living in the Mathare Valley in 2000 (40%) as compared to the 1998 KDHS population (22%). Using the 2000 US CDC growth grids as the standard, in this urban population stunting peaks at 12–23 months of age, with 71% considered stunted. Children, age twenty-three months and younger, living in the Mathare Valley slum, Nairobi, Kenya in 2000 appear to be at an increased risk for stunting compared to the population of Kenyan children in the 1998 KDHS survey.