Despite many years of effort and numerous programmes to improve the quality and safety of health care, major problems persist.1234567 Various reasons for the slow pace of improvement have been identified, such as resistance to change among health professionals, organisational structures that block improvement of care, and dysfunctional financial incentives.7891011 Many different approaches have been tried to speed up improvement, such as medical audit, evidence based guidelines, accreditation, disease management, public reporting of performance indicators, financial incentives, revalidation of professionals, and breakthrough collaboratives. Research on the effect of these approaches is scarce, but the evidence shows that even well developed improvement programmes are often only partially effective.8910 Despite substantial scientific development of this field, research on quality and safety in health care is not yet fully developed.11 We examine the reasons for the poverty of research in this field, and present the key challenges.