This is the protocol for a review and there is no abstract. The objectives are as follows: To examine the effectiveness and acceptability of all BT approaches compared with all other psychological therapy approaches for acute depressionTo examine the effectiveness and acceptability of different BT approaches (behavioural therapy, behavioural activation, social skills training and relaxation training) compared with all other psychological therapy approaches for acute depression.To examine the effectiveness and acceptability of all BT approaches compared with different psychological therapy approaches (psychodynamic, humanistic, integrative, cognitive-behavioural and third wave CBT) for acute depression.