BACKGROUND Educational meetings and printed educational materials are the two most common types of continuing education for health professionals. An important aim of continuing education is to improve professional practice so that patients can receive improved health care. OBJECTIVES To assess the effects of educational meetings on professional practice and health care outcomes. SEARCH STRATEGY We searched the Cochrane Effective Practice and Organisation of Care Group specialised register, MEDLINE (from 1966), the Research and Development Resource Base in Continuing Medical Education in January 1999 and reference lists of articles. SELECTION CRITERIA Randomised trials or well designed quasi-experimental studies examining the effect of continuing education meetings (including lectures, workshops, and courses) on the clinical practice of health professionals or health care outcomes. DATA COLLECTION AND ANALYSIS Two reviewers independently applied inclusion criteria, assessed the quality of each study, and extracted study data. We attempted to collect missing data from investigators. We conducted both qualitative and quantitative analyses. MAIN RESULTS Thirty-two studies were included with a total of 36 comparisons. The studies involved from 13 to 411 health professionals (total N= 2995) and were judged to be of moderate or high quality, although methods were generally poorly reported. There was substantial variation in the complexity of the targeted behaviours, baseline compliance, the characteristics of the interventions and the results. The heterogeneity of the results was best explained by differences in the interventions. For 10 comparisons of interactive workshops, there were moderate or moderately large effects in six (all of which were statistically significant) and small effects in four (one of which was statistically significant). For interventions that combined workshops and didactic presentations, there were moderate or moderately large effects in 12 comparisons (eleven of which were statistically significant) and small effects in seven comparisons (one of which was statistically significant). In seven comparisons of didactic presentations, there were no statistically significant effects, with the exception of one out of four outcome measures in one study. REVIEWER'S CONCLUSIONS Interactive workshops can result in moderately large changes in professional practice. Didactic sessions alone are unlikely to change professional practice.