This study reports relations between infant Ainsworth Strange Situation classifications, negative life events, and Adolescent Attachment Interview classifications. Overall, the stability of secure versus insecure classifications was 77%, and infant attachment classification was a significant predictor of adolescent attachment classification. Chi-square analyses indicate that negative life events are significantly related to change in attachment classification. The sample (n = 30) is drawn from the Family Lifestyles Project (FLS), an ongoing longitudinal study of children's development within the context of nonconventional family lifestyles. The distribution of family lifestyles within this study, unlike those in the full FLS sample, represent a higher proportion of conventional two-parent families (40%). There were no differences between adolescents reared in conventional or nonconventional families in the distribution of adolescent attachment security, the experience of negative life events, or the continuity of attachment from infancy through adolescence.