 Brief Summary: Persistent Physical Symptoms PPS; also known as medically unexplained symptoms - MUS is a term used to describe a range of physical health difficulties that people can experience and for which the exact cause is unclear. Between 20 and 40 of patients in primary care, and about 50 in secondary care experience PPS. Not only are PPS common, but the overlap across different patient groups may indicate that these phenomena are transdiagnostic. PPS are associated with profound disability and high health care costs, and if left untreated the prognosis of these patients is poor. There is an accumulating body of evidence demonstrating that cognitive behavioural interventions can reduce levels of symptoms and improve functioning in patients with PPS. A pragmatic RCT was designed to evaluate the clinical and cost-effectiveness of cognitive behavioural therapy CBT Standard Medical Care SMC versus Standard Medical Care alone, in the treatment of patients with PPS. The trial will focus on patients with a variety of symptoms e.g., non-cardiac chest pain, fibromyalgia, across secondary care clinics e.g., neurology, cardiology, and rheumatology. Patients who have been referred to secondary care in the past six months will also be recruited from General Practice GP surgeries. 