ABSTRACT: Acute coronary syndromes, including myocardial infarction and unstable angina, are important causes of premature mortality, morbidity and hospital admissions. Acute coronary syndromes consume large amounts of health care resources, and have a major negative economic and social impact through days lost at work, support for disability, and coping with the psychological consequences of illness. Several registries have shown that evidence based treatments are under-utilised in this patient population, particularly in high-risk patients. There is evidence that systematic educational programmes can lead to improvement in the management of these patients. Since application of the results of important clinical trials and expert clinical guidelines into clinical practice leads to improved patient care and outcomes, we propose to test a quality improvement programme in a general group of hospitals in Europe.This will be a multi-centre cluster-randomised study in 5 European countries: France, Spain, Poland, Italy and the UK. Thirty eight hospitals will be randomised to receive a quality improvement programme or no quality improvement programme. Centres will enter data for all eligible non-ST segment elevation acute coronary syndrome patients admitted to their hospital for a period of approximately 10 months onto the study database and the sample size is estimated at 2,000-4,000 patients. The primary outcome is a composite of eight measures to assess aggregate potential for improvement in the management and treatment of this patient population (risk stratification, early coronary angiography, anticoagulation, beta-blockers, statins, ACE-inhibitors, clopidogrel as a loading dose and at discharge). After the quality improvement programme, each of the eight measures will be compared between the two groups, correcting for cluster effect.If we can demonstrate important improvements in the quality of patient care as a result of a quality improvement programme, this could lead to a greater acceptance that such programmes should be incorporated into routine health training for health professionals and hospital managers.Clinicaltrials.gov NCT00716430.