The movement in recent years towards evidence-based practice (EBP) in health care systems and policy has permeated the substance abuse treatment system, leading to a growing number of federal and statewide initiatives to mandate EBP implementation. Nevertheless, due to a lack of consensus in the addiction field regarding procedures or criteria to identify EBPs, the optimal processes for disseminating empirically based interventions into real-world clinical settings have not been identified. Although working lists of interventions considered to be evidence-based have been developed by a number of constituencies advocating EBP dissemination in addiction treatment settings, the use of EBP lists to form policy-driven mandates has been controversial. This article examines the concept of EBP, critically reviews criteria used to evaluate the evidence basis of interventions, and highlights the manner in which such criteria have been applied in the addictions field. Controversies regarding EBP implementation policies and practices in addiction treatment are described, and suggestions are made to shift the focus of dissemination efforts from manualized psychosocial interventions to specific skill sets that are broadly applicable and easily learned by clinicians. Organizational and workforce barriers to EBP implementation are delineated, with corresponding recommendations to facilitate successful dissemination of evidence-based skills.