Effects of day care experiences on children's cognitive, emotional, and social/behavioral development were investigated by meta-analytic techniques. Thirteen studies meeting domain specifications were coded. Twenty variables including an effect size were coded for each study. Twenty-two levels of the dependent variable were identified, yielding 114 effect sizes from a sample population of 492 children. Results suggest that day care does not adversely affect children's behaviors or their development. The findings are consistent with previous reviews, while providing quantitative assessment of the effects of day care on children's development. The limitations and restrictions of the meta-analysis are also discussed. The meta-analysis codebook and a list of articles included in the analysis are appended. (Author/RH)