The term “quality tools” is used in many different ways to refer to a method used by an individual, a team, an organization or a health system. It is most often used in a narrow sense in American texts to refer to a set of simple “continuous quality improvement” methods (CQI tools). More broadly, it includes many other safety and quality methods, frameworks, programmes or systems. Some are diagnostic methods to help decision-making, some are for intervention and change only, and some include both methods for diagnosis and intervention.