Bipolar disorder (BD) is a common disease with a high burden related to frequent relapse and cognitive impairment. A significant factor in maintaining dysfunction and risk of relapse, is circadian rhythm disturbance. Psychotherapies have been developed which have been shown to impact upon this disturbance, and to reduce relapse, for example, Interpersonal and Social Rhythm Therapy (IPSRT). Recent evidence suggests that Bright Light Therapy (BLT) may also be helpful. However, patients rarely receive these therapies in clinical practice. Medications are usually the only treatment option available in mental health services, yet many patients have an inadequate response to these, which results in ongoing symptoms and relapse. We aim to evaluate, in a full study, the effectiveness of combined Social Rhythm Therapy (SRT) - a modified form of IPSRT - and BLT, in treating patients with ‘treatment resistant’ BD. Prior to embarking upon this, feasibility issues need to be clarified.