Cognitive-behavioural therapy (CBT) is the first-line treatment for panic disorder. Treatment is based on the idea that panic attacks occur as a result of an enduring tendency to misinterpret the symptoms of anxiety as a sign of an imminent catastrophe (e.g. palpitations meaning that the person is about to have a heart attack). Factors involved in the maintenance of such beliefs include selective attention to bodily sensations and the use of ‘safety-seeking behaviours’ (e.g. sitting down when the person thinks that they may faint during a panic attack). Cognitive treatment involves helping the person to understand how panic works and then testing their catastrophic beliefs through behavioural experiments (to discover that the things they are afraid of do not happen). Successful treatment involves panic inductions, helping the patient to drop their safety-seeking behaviour and reintroducing them to situations they have avoided, whist helping them to learn how panic is linked to their misinterpretations of the benign symptoms of anxiety. This treatment is highly effective, with low relapse rates. There is evidence that combining CBT with antidepressant medication does not result in better acute outcomes and is associated with considerably worse longer-term outcomes, with higher rates of relapse in combination drug and CBT treatment relative to CBT alone. Preliminary work suggests that intensive treatment, in which therapy takes place over a few days, is at least as effective as the more usual outpatient treatment over a period of weeks.