A process model of friendship formation in preadolescence is proposed in this article, and the continuity of early parent-child relationships (quality of attachment) with later friendship processes and peer competence is explored. Thirty-two preadolescents, subjects in a longitudinal study of attachment and subsequent social development, were observed in 4-week summer day camps. Those who had been securely attached with their caregivers as infants revealed a higher level of peer competence than did those with anxious attachment histories. However, preadolescents of both types of attachment reported and were observed to form friendships. In-depth case studies of four friendship pairs of preadolescents with different attachment histories suggested that there are corresponding differences in the quality and growth processes of those pairs of friendships. A three-stage model of preadolescent friendship growth is proposed, based on relationship dimensions and reflective of earlier relational patterns.