A phylogenetic propensity of human infants is to become attached. During ontogenesis, different qualities of attachment relationships develop. Caretakers’ responsiveness to infants’ signals of insecurity seems to be the main determinant of secure versus avoidantly or ambivalently insecure infant behaviors to mothers or fathers at 1 year of age. An individual's ‘inner working model’, resulting from differential dyadic attachment history, may determine how (inner) emotional conflicts are resolved. On the basis of existing longitudinal data, the following emotional response styles appear to be prevalent: Individuals with secure attachment histories pay attention to the full range of external causes for conflicting emotions, and they tolerate contradictory emotions. Individuals with insecure attachment histories, in contrast, pay attention only to selected fractions of their emotional reactions at any given time, and they tend to lose sight of the full range of external causes for potentially conflicting emotions. These developmental consequences appear to be universal. Cultural differences may exist in terms of frequency and difficulty of potentially conflicting challenges imposed on individuals. The wider view of attachment has to consider both aspects, the universal and the culture-specific, when testing the full potential of attachment theory from a life course perspective. © 1990 S. Karger AG, Basel.