Cognitive behavioural therapy (CBT) is based on several key principles: 1) thoughts influence emotions and behaviour, 2) behaviour also influences thoughts and emotions, 3) mental health problems are exaggerations of normal cognitive and behavioural processes. CBT focuses on identifying and modifying dysfunctional thoughts and behaviours in the present. Techniques include cognitive restructuring like identifying cognitive distortions, behavioural experiments, and modifying core beliefs through empirical testing. Physical techniques like relaxation can also be used.