Links between maternal emotional reactions to crying (anger and anxiety) and infant attachment security were examined in 119 mother-infant dyads. Mothers rated the intensity of their emotional responses to videotapes of crying infants prenatally. Maternal sensitivity was observed during infant exposure to emotion eliciting tasks at six and 16 months postpartum and mothers' self-reported on their responses to their infant's negative emotions at 16 months. Infant attachment security was assessed using the Strange Situation at 16 months postpartum. Results indicated that observed sensitivity was associated with fewer avoidant and resistant behaviors and prenatal maternal anger and anxiety in response to infant crying predicted the developing attachment system independent of observed sensitivity, but in different ways. Maternal anxiety in response to crying was positively associated with resistant behaviors as a direct effect. Maternal anger in response to crying was associated with avoidant behaviors indirectly through mothers' self-reported punitive and minimizing responses to infant distress at 16 months. Theoretical, applied, and methodological implications are discussed.