This chapter focuses on the characteristics, dynamics, and effects of adolescent friendships. It examines the peer groups that adolescents can be part of. The chapter highlights the peer relations in terms of the social status will be highlighted. It describes bullying and victimization, as a specific kind of negative peer relations. The chapter also describes that although peer relationships become increasingly important in adolescence, the parent-adolescent relationships are still significant for adolescents’ lives. Friendships are characterised by reciprocity and commitment between two individuals who see themselves similar in feelings and orientations. Adolescents recognize that conflicts can irreparably damage their friendships. They also recognize, however, that conflicts can have positive effects in that conflicts provide opportunities for friendship growth and improvement of the relationship. Youth cultures not only influence the opportunities for acquiring positive social skills but they also affect adolescent health behaviors, either by fostering health-enhancing or healthcompromising behaviors.