ISSUE: Will Precision Medicine result in health care rationing? From genomics to patient centered care, payers, health systems and government will have to consider new approaches in making coverage and payment decisions, while personalizing medical treatment for patients. High quality transparent research on the value of precision medicine is needed to inform clinical and coverage decisions. Recent advances in genetic testing technology have created a dilemma for payers: What health technology assessment methods are appropriate to decide when a particular test should be covered? Current evidence may suffice to determine the clinical validity of a test, but not necessarily the clinical utility, which in turn is required to determine cost-effectiveness. How much evidence should we require, and what must we accept in faith? Evidence-related challenges will be actively argued to provoke discussion on developing new practices and modeling to create precision medicine evidence relevant to decision makers. OVERVIEW: Continued advancement in the discovery of breakthrough therapies increasingly depends on adapting those therapies to target populations, and individuals, taking into account variations in genetics, epidemiology, environment, lifestyle and behavior. Many diseases still do not have proven approaches to prevention or effective treatments. There is a dire need to gain better insights into the biological, environmental, and behavioral influences on these diseases to be able to more systematically improve outcomes. This effort leads to better selection of disease targets and identification of patient populations that demonstrate improved clinical outcomes. The new field presents an opportunity and a challenge for outcomes research, as it changes the parameters of what to consider when assessing the value and cost, and cost effectiveness of therapies.