The effect of early prenatal dexamethasone (DEX) exposure on cognitive and behavioral development, behavior problems, and temperament were examined in 26 consecutively identified children aged 6 mo to 5 1/2 years, whose mothers had been DEX-treated during pregnancy because their offspring was at risk for congenital adrenal hyperplasia (CAH), and compared with 14 children from untreated CAH-risk pregnancies. Three children in each group were CAH-affected. Assessments were performed by way of mother-completed standard questionnaires. No significant differences in cognitive abilities or behavior problems were identified. On temperament questionnaires, DEX-exposed children showed more Shyness (p < .004), greater Emotionality (p < .03), less Sociability (p < .04), and a trend for greater Avoiddance (p < .07) than unexposed children. DEX-exposed children also had significantly higher Internalizing (p < .002) and Total Problem scores (p < .05) on the behavior problem measure for 2-3 year olds. The results should be considered preliminary until they have been replicated by the study of a larger sample and direct examination of the children.