Background/Objective: Adolescents with a visible difference can experience challenging social situations, (e.g., people staring or making unwanted comments) and are at risk for mental health problems. Interventions for adolescents with a visible difference experiencing appearance-related distress are scarce and lack an evidence-base. Therefore, YP Face IT was developed. This psychosocial eHealth intervention combines social skills training and cognitive behavioural therapy to help adolescents cope with challenging social situations and difficult thoughts. Method: To assess acceptability and feasibility 15 Dutch adolescents aged 12-17 completed YP Face IT and participated in in-depth interviews. Responses were analysed using thematic analysis. To assess effectiveness 189 Dutch and Norwegian adolescents participated in a Randomised Controlled Trial and were randomly allocated to YP Face IT or Care As Usual (CAU). Outcomes were body esteem, social anxiety, perceived stigmatisation, and life disengagement. Outcomes were measured at baseline and direct follow-up. Results: Acceptability and feasibility: Most adolescents appreciated the intervention and all would recommend it to other adolescents with a visible difference experiencing appearance-related distress. Effectiveness: Compared to CAU, participants who completed YP Face IT showed reductions in social anxiety. No significant results were found for the other outcomes. Conclusions: Both studies show that YP Face IT is acceptable, feasible and effective for adolescents with a visible difference. Dutch adolescents endorsed YP Face IT and its components. International results show that YP Face IT reduces social anxiety. Future studies are needed to confirm the effectiveness of YP Face IT and to explore potential long-term effects.