Background: Meals served at government-run day care centers must be nutritionally adequate to ensure good health and proper development of preschool-aged children. They can provide a controlled opportunity to complement the daily diet of children in vulnerable populations. Objective: To determine the nutrient adequacy and leading food sources of nutrients provided by the diet served in government-sponsored day care centers. Methods: Estimated daily energy and nutrient intakes of a theoretical 40-day day care center menu were calculated, and the nutrient adequacy was assessed. Nutrient densities and critical nutrient densities of the menu were computed to identify nutrient inadequacies. Furthermore, main sources of nutrients were identified, and energy and nutrient distributions were examined by meal time. Results: The menu provides approximately 90% of daily energy requirement and more than 100% of Recommended Nutrient Intakes (RNIs), with the exception of vitamin D and calcium. Sugar was the first leading source of energy, whereas milk was the first leading contributor of vitamin D. Conclusion: Within an environment of budgetary constraints, the Guatemalan government developed and advocated an exemplary menu offering for children in the vulnerable preschool period. We have demonstrated that, if prepared and served as planned, the items from the official, standard menu would supply most of the nutrients needed. High vitamin A intake related to the mandated national fortification program is a potential problem. From the analysis, it was found that vitamin D emerges as the most prominent candidate for a problem nutrient of deficient intake. (author abstract)