This review looked at how effective different psychological "talking" therapies were at preventing relapse of depression. It found that cognitive behavioural therapy, mindfulness-based cognitive therapy and interpersonal psychotherapy all reduced the risk of depression relapse over a year by 20 to 25% compared with a control treatment. There was further evidence that the effect for cognitive behavioural therapy was sustained up to two years. This reinforces NICE guidance, which recommends that cognitive behavioural therapy or mindfulness-based cognitive therapy be offered to people at risk of a relapse of depression. The trial results suggested factors like participant characteristics and treatment delivery affected treatment success. These results may help therapists further tailor their treatment approaches within the NHS Improving Access to Psychological Therapies programme.