The Conference on the Science of Dissemination and Implementation in Health (D&I),  co-hosted by the National Institutes of Health (NIH) and AcademyHealth, helps realize the full potential of evidence to optimize health and health care by bridging the gap between research, practice, and policy. By outlining the priorities in the still emerging field of D&I Science, this conference aims to ensure that evidence is used to inform decisions that will improve the health of individuals and communities.