This study examined the effects of early vs. extended mother-infant contact on infant, maternal and interactional outcomes in the lying-in period for 104 lower class mother-infant dyads. The early contact treatment consisted of placing the mother and neonate together for 10 to 45 minutes within the first 3 postpartum hours. The extended contact treatment provided mother-neonate contact in a roomin-in situation for approximately 10 hours per day of the lying-in period. Utilizing a 2 (early contact) x 2 (extended contact) x 2 (sex of the infant) unequal cells factorial design, 104 lower class primiparas and their health, full-term neonates were assigned to one of eight possible cells in a manner as unbiased as hospital contraints would permit. Because sex effects were slight and insignificant to the data reported here, the design was collapsed into a 2 (early contact) x 2 (extended contact) and analyzed as othogonal contrasts. Dependent variables included observations of mothers and infants during the fourth and fifth lying-in feedings. In addition, was evaluated using the Brazelton Neonatal Behavioral Assessment Scale and mothers were given a multiple-choice questionnaire on their infant's temperament. Results for infant, maternal and interactional variables supported the importance of immediate postpartum contact between mother and infant in facilitating mother-infant adaptation. Some support was also provided for extended postpartum mother-infant contact. (Author/JMB)