Objective: Youth with ADHD experience significant impairment in peer functioning. Based on recommendations from the literature, the current pilot study examined the effectiveness of a parent-assisted, friendship-building program at establishing mutual friendships and improving peer relationships in adolescents with ADHD. Method: Participants included 20 adolescents with ADHD (ages 11-16 years) and their parent(s). Families completed the Program for the Evaluation and Enrichment of Relational Skills (PEERS). Measures of friendship quality, social knowledge, social self-efficacy, get-togethers, and peer conflict were completed at baseline and post-treatment. At post-treatment, participants also reported on the initiation of a new friendship. Results: Baseline to post-treatment differences were examined using paired-samples t tests. The majority of participants reported the initiation of a new friendship at post-treatment. Adolescents also demonstrated significantly improved social knowledge and increased get-togethers. Effect sizes were large. Conclusion: Following participation in PEERS, adolescents improved in several peer functioning domains and many initiated new friendships.