The magnitude and potential causes of linear growth retardation in a rural agricultural community of the Ecuadorian Andes are examined. Growth stunting is common in this population, as height-for-age Z-scores (HAZ) for boys and girls 1-5 years average -2.2 and -2.0, respectively. Dietary analyses suggest multiple nutrient deficiencies. The diet appears to be moderately deficient in energy, protein, calcium, and vitamin A, and more severely limiting in zinc. Additionally, analyses of the local water supply and household hygiene indicate that risk of infection is relatively high among this population. Of the 23 days for which water quality was monitored, slight Escherichia coli contamination was observed on 13 days (57%), and moderate contamination was seen once (4%). Overall, it appears that growth faltering in this population reflects the synergistic effect of mild-to-moderate malnutrition and disease. It is unlikely that malnutrition alone is sufficient to explain the degree of stunting seen in this and other Andean populations. Rather, the stress of coping with chronic disease in the presence of malnutrition may contribute to early childhood growth faltering and compromise potential catch up growth later in life. Am. J. Hum. Biol. 10:229-240, 1998. Β© 1998 Wiley-Liss, Inc.