Objectives: To develop a cognitive behavioral intervention for adolescents with bipolar disorders, test its feasibility and preliminary efficacy. Methods: Based on existing research, a manualized, individually delivered cognitive behavioral intervention was developed and tested with adolescents with bipolar disorders as an adjunct to pharmacological treatment. Using existing data, baseline characteristics and outcome were compared to a matched group of eight adolescents with bipolar disorders who did not receive any psychosocial intervention. Results: Preliminary results support the feasibility and efficacy of this manualized cognitive behavioral intervention. Conclusions: Individually delivered cognitive-behavioral therapy (CBT) as an adjunct to pharmacological treatment is feasible and associated with symptom improvement in adolescents with bipolar disorders. Randomized controlled studies are needed.