OBJECTIVES: Suicide is the second leading cause of mortality among Canadian youth. As wait times for mental health (MH) support have increased, adolescents with mild-to-moderate suicidal ideation (SI) are waiting longer for support compared to those with more acute SI. Building Resilience and Attachment in Vulnerable Adolescents (BRAVA) is a 6-week virtual group intervention designed to provide support to adolescents with mild to moderate SI and their caregivers. We conducted a randomized controlled trial to assess the efficacy of BRAVA in reducing symptoms of SI, depression, and anxiety in adolescents, and improving life stress in caregivers. DESIGN/METHODS: Outcome measures were administered to both groups [BRAVA, Enhanced Treatment-as-Usual (ETU)] at intake and exit, and at 3-month follow-up (BRAVA only) for SI (primary outcome), anxiety and depression (adolescent), perceived stress (youth and caregiver), attachment and family functioning (caregiver). SI was measured using Suicidal Ideation Questionnaire Junior. Intention to treat (ITT) analysis was performed for youth and caregiver cohorts. RESULTS: Ninety-nine eligible youth presenting with mild-to-moderate SI and their caregivers were recruited from hospital and community MH services. Families were randomized to BRAVA (n = 50) or ETU (n = 49). Adolescents were on average 14.6 years old, mostly female (64%), and of European racial heritage (44%). In ITT analysis, both BRAVA and ETU groups improved in youth SI from intake to exit, with no statistically significant differences between groups at exit. Sensitivity analysis without multiple imputations demonstrated a significant difference in SI scores at exit between the groups, where improvements in the BRAVA group were maintained at 3-month follow-up. Significant differences between groups on youth perceived stress, and depression and anxiety scores were also observed in BRAVA participants at post-treatment compared to the ETU control group. No statistically significant differences were observed for any caregiver outcomes measured except a trend for improved perceived caregiver stress in the BRAVA group post-treatment. CONCLUSIONS: BRAVA was associated with significantly greater improvements in anxiety/depression and adolescent perceived stress compared to ETU. Although the intervention did not result in significant caregiver reported improvements, group cohesion and treatment satisfaction were high for both youth and caregivers. CLINICAL TRIAL REGISTRATION: BRAVA: Building Resilience and Attachment in Vulnerable Adolescents (BRAVA); https://clinicaltrials.gov/ : NCT04751968.