Subclinical vitamin A deficiency was assessed in 65 Hispanic children attending four migrant Head Start programs in Utah. Subjects aged 2 to 6 years (median 3 years 10 months) were examined for evidence of vitamin A deficiency by conjunctival impression cytology. Biochemical indices for serum vitamin A, retinol-binding protein, zinc, and iron were performed. Of eight children (12.5%) with subclinical vitamin A deficiency, one child had a marginal serum vitamin A of 11 μg/dl. Retinol-binding protein concentrations were significantly lower in two subjects with abnormal conjunctival impression cytology. Serum zinc, which when low can mimic signs of ocular vitamin A lesions, was normal for all 65 subjects. Fifteen children (23%) had iron-deficiency anemia. Logistic regression was the central method of analysis used in this study. The results of the statistical analyses indicated there was a correlation value (0.31) between abnormal conjunctival impression cytology and serum vitamin A, which supports the hypothesis that abnormal conjunctiva! impression cytology is concurrent with decreased serum vitamin A. Assessment of vitamin A status of Hispanic migrant children by impression cytology was effective in identifying children at risk for hypovitaminosis A. Beyond vitamin A's role in vision and maintenance of epithelium, it is also required for growth and hematopoiesis. The children of migrant workers may be suffering physiologically important consequences of vitamin A and iron deficiency that can be prevented by screening with biochemical and histological testing. Nutrition intervention for deficient children is warranted.