Sensitivity to interpersonal timing was assessed in mother–infant interaction. In Study 1, 3-month-old infants interacted with their mothers over television and the mothers’ audio-visual presentation was either live or temporally delayed by 1 second. Infants gazed longer when the mother was presented live compared to delayed by 1 second, indicating that they detected the temporal delay. In Study 2, mothers interacted with their 3-month-old infants over television and the infants’ audio-visual presentation was either live or temporally delayed by 1 second. (...) Mothers’ behavior was not altered by a 1-second delay in their infants’ behavior compared to a live presentation. In Study 3 and 4, the results were replicated with 6-month-old infants. Whereas infants detected the temporal delay in maternal responses, mothers likely adjusted to the delay in infant behavior. The discussion focuses on the role of interpersonal timing for detecting social contingency in dyadic and triadic communication. (shrink)