Non-A, non-B hepatitis (hepatitis C) is a viral infection(s) transmitted mainly by blood and blood products. Infection is usually asymptomatic, but typically followed by chronic infection, frequently with chronic liver disease. Although probably less than 1% of the UK population (and hence dental patients) are infected, groups at high risk for other blood-borne infections are also at risk for non-A, non-B hepatitis. Immunisation against hepatitis B cannot protect against non-A, non-B hepatitis; recommended cross-infection procedures must suffice to protect patients and staff.