How can we encourage ongoing development, refinement, and evaluation of practices to identify and build an evidence base for best practices? On the basis of a review of the literature and expert input, we worked iteratively to create a framework with 2 interrelated components. The first - public health impact - consists of 5 elements: effectiveness, reach, feasibility, sustainability, and transferability. The second - quality of evidence - consists of 4 levels, ranging from weak to rigorous. At the intersection of public health impact and quality of evidence, a continuum of evidence-based practice emerges, representing the ongoing development of knowledge across 4 stages: emerging, promising, leading, and best. This conceptual framework brings together important aspects of impact and quality to provide a common lexicon and criteria for assessing and strengthening public health practice. We hope this work will invite and advance dialogue among public health practitioners and decision makers to build and strengthen a diverse evidence base for public health programs and strategies.