Nonviolent resistance parent training (NVR) focuses on helping parents resist the child's negative behaviors without escalating the problem. NVR helps parents to fulfill an anchoring function, supporting the child through presence, self-regulation, structure, and support network. The study was a randomized controlled trial designed to assess the efficacy of NVR in the treatment of childhood ADHD. Participants were parents of children with primary ADHD diagnosis (N = 101; 5-13 years old; 79% male participants) randomly assigned to either 12-session NVR (N = 50) or waiting list (N = 51). Measures were administered before and after treatment and at a 4-month follow-up. ADHD outcomes included the Conners and Child Behavior Checklist. Parenting outcomes included parental helplessness, emotional regulation, anchoring function, and family chaos. Participants in the NVR condition reported significant improvements in the child's internalizing, externalizing, and ADHD symptoms, as well as improvement in paternal and maternal helplessness and anchoring. Participants in the control condition did not report changes in the child's symptoms or the parents' condition. The results at follow-up revealed maintenance of change in the child's externalizing behavior as expected, but more surprisingly in their internalizing symptoms as well including depression and suicidal tendencies . Maternal helplessness and anchoring, as well as family chaos continued to improve at follow-up. Dropout rates in the treatment group were low (5%), and fathers' engagement was close to 100%. In a second confirmatory study which made an extensive effort to ensure blindness of researchers on a new sample of 181 children NVR also contributed significantly to a reduction in depression and suicidality