This article describes the use of microanalysis of videotapes to look at nonverbal elements (such as smiles, facial expressions, eye gaze, touch, and head and body movements toward and away from the other) to determine the caregiver-infant interactive (regulatory) experience. Video microanalysis of face-to-face play by infants and parents illustrates varying interactions of maternal intrusion and infant avoidance. In one sense, infant aversion and withdrawal are completely usual: All infants look or turn away from time to time. At other times, such behavior may be viewed as extreme, particularly when parents engage in overstimulation and intrusion. The behavioral process of one partner can be predicted from that of the other partner. Maternal intrusion and infant withdrawal is a co-constructed process between mother and infant.