Both the Institute of Psychiatry, Psychology and Neurosciences at King’s and TUD are partners in the large international multisite study to identify biomarkers for the response of patients with bipolar disorder to lithium. Participants will be both phenotyped utilizing resting state fMRI, actimetry and instruments to quantify psychopathology and genotyped. The quality of response to lithium will be assessed after two years of continuous follow up. For more information, visit the Website.