Research Findings: This study examined factors associated with process and content outcomes of the training provided in the context of Head Start REDI (Research based Developmentally Informed), a preschool curriculum designed to enhance the quality of interactions (social-emotional and language-literacy) between teachers and children. REDI professional development included 4 days of training and weekly coaching. Data for 22 intervention teaching pairs (N = 44) were used in the study. With the exception of years of education and emotional exhaustion, distal teacher factors (i.e., professional characteristics, personal resources, and perceptions of the work environment) were unrelated to implementation fidelity, whereas openness to consultation showed a significant association. Practice or Policy: The findings emphasize the importance of teacher engagement in the training process for program effectiveness. (Contains 2 figures and 4 tables.)