To elucidate the differential saliency of infant emotions to mothers across interactive contexts, the authors examined the moderating role of observed infant affect during interactions with mother in the relation between maternal and laboratory-based ratings of infant temperament. Fifty-nine developmentally healthy 9-month-old infants were judged for degree of infant positive, infant negative, and mother-infant mutually positive affect during the course of object-focused and routine home-based activities with mother. Mothers completed the Infant Behavior Questionnaire (M. K. Rothbart, 1981), and infants underwent the Laboratory Temperament Assessment Battery (H. H. Goldsmith & M. K. Rothbart, 1999). Results revealed that maternal and observer ratings of infant negativity converged when infants manifested high degrees of negative affect during routine home-based activities. Maternal and observer ratings of infant positivity converged when infants experienced low mutually positive affect during play. These findings support the hypothesis that maternal perceptions are based on mothers' experiences with their infants but that the salience of infant temperamental characteristics to mothers varies across emotion and interactive context.