Youth mental health has become a critical public health concern in urban Nigeria, with adolescent depression rates on the rise. Existing programmes have shown mixed effectiveness. The analysis employs a longitudinal data set from urban Nigeria, utilising both qualitative and quantitative methods to assess programme implementation and efficacy. Findings indicate that although some programmes showed promise, the overall reduction in adolescent depression was modest—only 15% of participants reported significant improvement in depressive symptoms. Despite limited effectiveness, this study highlights the need for continued research into effective mental health interventions for adolescents in urban Nigeria. Further research should focus on refining and expanding existing programmes to achieve more substantial reductions in adolescent depression rates.