The effect of mother-infant skin-to-skin contact (kangaroo care, or KC) on self-regulatory processes of premature infants was studied. Seventy-three infants who received KC were compared with 73 infants matched for birth weight, gestational age, medical risk, and family demographics. State organization was measured in 10-s epochs over 4 hr before KC and again at term. No differences between KC infants and controls were found before KC. At term, KC infants showed more mature state distribution and more organized sleep-wake cyclicity. At 3 months, KC infants had higher thresholds to negative emotionality and more efficient arousal modulation while attending to increasingly complex stimuli. At 6 months, longer duration of and shorter latencies to mother-infant shared attention and infant sustained exploration in a toy session were found for KC infants. The results underscore the importance of maternal body contact for infants' physiological, emotional, and cognitive regulatory capacities.