Little is known about the quality of clinical care provided outside the hospital sector, despite the increasingly important role of clinical generalists working in primary care. In this study we aimed to summarise published evaluations of the quality of clinical care provided in general practice in the UK, Australia, and New Zealand. A systematic review of published studies assessing the quality of clinical care in general practice for the period 1995-9. General practice based care in the UK, Australia, and New Zealand. Main outcome measures-Study design, sampling strategy and size, clinical conditions studied, quality of care attained for each condition (compared with explicit or implicit standards for the process of care), and country of origin for each study. Ninety papers fulfilled the entry criteria for the review, 80 from the UK, six from Australia, and four from New Zealand. Two thirds of the studies assessed care in self-selected practices and 20% of the studies were based in single practices. The majority (85.5%) examined the quality of care provided for chronic conditions including cardiovascular disease (22%), hypertension (14%), diabetes (14%), and asthma (13%). A further 12% and 2% examined preventive care and acute conditions, respectively. In almost all studies the processes of care did not attain the standards set out in national guidelines or those set by the researchers themselves. For example, in the highest achieving practices 49% of diabetic patients had had their fundii examined in the previous year and 47% of eligible patients had been prescribed beta blockers after an acute myocardial infarction. This study adopts an overview of the magnitude and the nature of clinical quality problems in general practice in three countries. Most of the studies in the systematic review come from the UK and the small number of papers from Australia and New Zealand make it more difficult to draw conclusions about the quality of care in these two countries. The review helps to identify deficiencies in the research, clinical and policy agendas in a part of the health care system where quality of care has been largely ignored to date. Further work is required to evaluate the quality of clinical care in a representative sample of the population, to identify the reasons for substandard care, and to test strategies to improve the clinical care provided in general practice.