Mechanisms of change in cognitive–behavioural therapy: implications for clinical practice

SUMMARY Cognitive–behavioural therapy (CBT) developed from two traditions: behavioural methods grounded in learning theory, and cognitive models that explain emotional distress through appraisals and beliefs. Contemporary practice integrates both at the level of formulation and technique: behavioural methods such as exposure and behavioural activation can change cognition, while cognitive strategies can support behavioural change. The empirical picture is more complex. Component studies suggest that behavioural interventions alone often produce outcomes comparable to full CBT, while the mediating role of cognitive change remains debated. This article reviews both traditions, describes how contemporary accounts of exposure (including inhibitory learning and expectancy violation) and behavioural experiments integrate them and considers what component and process research in social anxiety disorder and depression reveals about mechanisms of change. We argue for formulation-driven CBT, selecting cognitive strategies, behavioural strategies or both, according to the presentation, patient capacities and preferences, and treatment stage. Fictitious vignettes illustrate this approach, including adapted CBT for people with an intellectual disability.