Epidemiology is at the center of translational science. Uniquely among biomedical disciplines, the methods and perspective of epidemiology span research from discovery to effective interventions and ultimately to their dissemination and implementation. However, shorthand designations for various phases of translational science, such as "T1, T2, T3, and T4," may be proliferating past the level of their usefulness. It is worthwhile to reflect on the actual nature of the science undertaken by epidemiologists along the continuum of discovery to application. The new challenge for epidemiology is the integration of knowledge and effective interventions into various societal settings working with allied disciplines not necessarily in the biomedical domain to ensure that these interventions have their intended effects on individual and public health.