Background: The Cochrane Effective Practice and Organisation of Care Group (EPOC) supports systematic reviews of professional, organizational, financial, and regulatory interventions to improve health care delivery and care systems. Since 2007, EPOC has worked with the Canadian Agency for Drugs and Technologies in Health (CADTH) to publish and update a website summarizing reviews of interventions to improve evidence-based prescribing practice and drug use. Objectives: To collect and summarize in an overview, interventions targeting prescribing and other professional behaviours. Methods: Systematic reviews published between 1966 and 2009 were identified from Medline, Embase, and The Cochrane Library. Two reviewers abstracted data from the reviews. Vote counting was used as the common metric for data synthesis. Interventions were classified as effective if more than two-thirds of included studies showed benefit. Reviews that were of moderate to high quality were included in the analysis. All relevant reviews are available at: www.rxforchange.ca. Results: Over 300 reviews were identified; 150 met the quality criteria and addressed professional, organisational, financial or regulatory interventions. Generally effective interventions included printed educational materials, interactive educational meetings, educational outreach, local opinion leaders, and audit and feedback. There were eight high-quality reviews addressing multi-faceted interventions. Five of the identified intervention categories (all within organizational categories) contain no reviews. Conclusions: A number of interventions are generally effective for changing professional behaviour. For those interventions where data are not available, efforts should be made to conduct reviews to assess the effectiveness.