Contextual fit is a construct that has gained increased attention from those who implement evidence-based interventions across education and human services domains. Contextual fit is based on the premise that the match between an intervention and local context affects both the quality of the intervention implemented and whether the intervention actually produces the outcomes desired for the children and families receiving the intervention. Although contextual fit is not new, an operational definition, formal measures, and systematic research that guides both policy and practice are needed before assessing the fit of evidence-based interventions for a particular context can become common practice. We encourage current implementers to incorporate efforts to assess and adapt contextual fit into the interventions they intend to adopt. More importantly, we encourage the formal development of measurement technology and experimental studies that can further define the role of contextual fit in implementation science.