Caregivers' practices concerning oral rehydration of young children during diarrheal illness were investigated in a periurban community of low socioeconomic level in Lima, Peru. Data of 330 caregivers of children aged 6-36 months were analyzed; 72.7% of all caregivers would give commercially available oral rehydration solutions (ORSs). However, only 58.6% of those caregivers with children that had experienced diarrhea during the previous week stated that they had used commercially available ORSs, a significantly lower percentage. The main reason for not using commercially available ORSs was that caregivers did not know about them. Of all recipes caregivers provided for homemade ORS, none contained the recommended concentrations of sugar and salt. Educating caregivers about availability, benefits, and use of commercially available ORSs as well as correct preparation of homemade ORS is urgently needed.