The authors argue that depression is characterised by interconnected biases across several stages of information processing, including attention, interpretation, memory, and cognitive control. Rather than operating in isolation, these biases may reinforce one another and collectively increase vulnerability to depressive symptoms. The review highlights emerging evidence that combinations of biases may better predict depression than any single bias alone, although further research is needed to clarify the nature of these relationships. Overall, the paper extends the combined cognitive bias hypothesis to depression and provides a framework for understanding how multiple cognitive processes interact to sustain emotional difficulties.