Despite the growing knowledge base on evidence-based practices in social work and medicine, there is a large gap between what is known and what is consistently done. Implementation research is the study of methods to promote the uptake of research findings into routine practice. In this article, we describe the rationale for implementation research and outline the concepts and effectiveness of its practices. Despite a large number of systematic reviews of implementation interventions, many of the fundamental questions regarding what approaches should be used in which settings for which problems remain unanswered. We go on to argue that future implementation studies should assess the context of practice and key features of interventions to better inform service quality improvement efforts.