Depression is a serious mental health problem that affects millions. Depression is usually treated using drugs and/or psychotherapy, but neither approach is successful for everyone, and some people do not respond to either. Therefore it is crucial that we continue to seek new methods for treating depression, and develop enhancements to existing treatments. In recent years, trials have documented improvements in depressive symptoms using noninvasive brain stimulation techniques, such as transcranial direct current stimulation, or tDCS. Our aim in this research is to investigate the effects of brain stimulation combined with psychological therapy in depression, an area that remains largely unexplored. Specifically, stimulation of the dorsolateral prefrontal cortex (DLPFC), a brain region known to work inefficiently in depression, has been shown to result in an improvement of depressive symptoms, as well as in the patient's 'cognitive control' abilities. Because 'cognitive control' processes, such as concentrating and ignoring distracting thoughts, are engaged during psychological therapies for depression, we predict that DLPFC stimulation should improve how patients respond to psychological therapy. This study has considerable implications as it will potentially benefit a large number of patients for which current treatments are ineffective.