Chronic diseases are long-term conditions that cannot be cured but can be controlled with medication and/or other therapies (DoH 2010). Examples include coronary heart disease (CHD), stroke, cancer, chronic respiratory diseases and diabetes, which together constitute the leading cause of mortality worldwide (60 per cent of all deaths) and are projected to increase by a further 17 per cent over the next 10 years (WHO 2010). In addition to the human cost however, chronic diseases place a heavy economic burden on healthcare systems. In England, there are currently 15.4 million people living with a chronic condition (DoH 2010), accounting for more than 50 per cent of all general practitioner appointments, 65 per cent of all outpatient appointments and over 70 per cent of all inpatient bed days (DoH 2010).The treatment and care of individuals with chronic disease accounts for 70 per cent of the total health and social care costs, and this is projected to rise dramatically over the next 12-15 years as the number of people aged over 65 years increases by an estimated 42 per cent (DoH 2010).In the USA, more than 109 million people report having at least one of the seven most common chronic conditions (CHD, hypertension, stroke, pulmonary conditions, cancer, diabetes, mental disorders), representing more than half the population, and a figure which is expected to increase by 42 per cent by 2023 (DeVol and Bedroussain 2007). The total impact of these diseases on the American economy is estimated to be $1.3 trillion annually ($1.1 trillion due to lost productivity and $277 billion spent annually on treatment). Table 1.1 shows 12 prevalent chronic disease conditions.