An evidence-based approach to professional development used to promote Head Start teacher adoption of evidence-based early childhood intervention practices is described. The article, includes a summary of findings from a meta-analysis of adult learning methods, a description of an approach to professional development informed by the meta-analysis results, and a description of how the approach was used to provide training to teachers in 18 Head Start classrooms. An evaluation of the professional development approach in the Head Start classrooms found that it was associated with differences in teacher adoption and use of the child learning opportunities and teacher instructional practices constituting the focus of training. Implications for professional development in early childhood programs are described. (Contains 4 figures and 6 tables.)