On December 2-3, 2010, the National Institutes of Health and the Agency for Healthcare Research and Quality are co-sponsoring a conference on “Methodological Challenges in Comparative Effectiveness Research.” The meeting will explore new methodologic, design and evidentiary approaches that can help “ensure the credibility, validity and reliability of applicable research findings to a diverse population, and to assist practitioners, patients and policymakers to come to the right personalized decisions.” Among other things, the conference will review case studies on particular treatments for medical conditions that pose difficult questions about what kinds of research, methods, and analyses should be used to address limitations in current evidence for interventions and tests being examined by decision-making bodies. The registration deadline is November 17, 2010.