Randomized Controlled Trial of Functional Family Therapy for Offending and Antisocial behaviour in UK Youth [running head: RCT of FFT ]

Background: Youth offending and antisocial behavior (ASB) are associated with low quality mental health and relationships and usually lead to poor adult functioning; they are very costly for society. Family interventions are effective in children but there are few reliably effective and inexpensive interventions for adolescents. Functional Family Therapy (FFT) is an evidence-based intervention but seldom tested outside the US. Methods: 111 adolescents (10-17 years of age, M = 15.0, SD = 1.63) and their families were randomized to FFT + Management As Usual (MAU) (n=65) or to MAU