Panic disorder remains a major health problem associated with high levels of disability and medical care, compounded by difficulties accessing appropriate treatment. Despite significant advances in understanding and effective treatment with CBT, the scope for better recognition and early intervention to prevent panic disorder has been relatively neglected in the CBT literature. This pilot study utilized the prevalence of panic attacks presenting in emergency medical care to test deployment of CBT as a practical early intervention strategy for panic disorder in routine NHS conditions. Twenty-seven people attending two typical UK Accident & Emergency (A&E) Departments with recent onset panic attacks were given a single session of CBT-based intervention or assessment only, and followed-up over 3 months. Basic measures of panic symptoms showed an improving trend across the whole sample. The very limited experimental control did not permit firm conclusions about the role of the intervention but at follow-up nearly one-third reported persisting difficulties typical of panic disorder, which then improved with brief additional CBT. Implications are discussed in relation to the existing literature and regarding further research on panic disorder prevention.