Background/AimsThe persistence of residual depressive symptoms (RDS) among patients in clinical remission predicts a negative prognosis and is considered an important target for adjunctive treatment. Mindfulness-Based Cognitive Therapy (MBCT) is effective in reducing RDS. Delivered in 8 in-person group sessions, MBCT teaches disengagement from depression-related ruminative thought patterns to reduce RDS and vulnerability to relapse. However, MBCT faces barriers to dissemination including service costs and access. We developed an 8 session web-based version of MBCT (Mindful Mood Balance, or MMB), incorporating experiential practice, video-based vicarious learning, and didactic information that replicate core components of in-person MBCT.