AbstractPlay interactions between 36 college‐educated, middle‐income, working mothers and their infants, who had attended nursery school since 1 month of age, were videotaped when the infants were 12, 18, and 24 months of age. The videotapes were coded for mother and infant looking at each other, vocalizing, affectionate play, and constructive play. Changes noted in the infants' play behaviors across this period included an increase in infant vocalizations and constructive play and a decrease in affectionate play. These results, together with corresponding decreases in the mothers' constructive and affectionate play behavior, suggest growing autonomy of the infants' play and encouragement of autonomy by the mothers. Stability of behaviors across this period and stability of relations between infant and mother behaviors were only moderate. Comparison of these data with data from a study by Clarke‐Stewart and Hevey (1981) suggested greater frequency of interactive behavior among working mothers and their infants than among nonworking mothers and their in