Early childhood programs are increasingly using new curricula that emphasize skills related to school readiness. It is the teachers in these programs who have the major responsibility for implementing a new curriculum and for sustaining its use. In this study, we interviewed 43 Head Start and prekindergarten teachers to see how many teachers continued to use Children's School Success (CSS), a research-based curriculum, after 1 year of implementation. Seventy-two percent of the teachers continued to use all or portions of CSS, and the remainder of the teachers did not use it. Through our interviews, we identified factors that contributed to teachers' continuing curriculum use. These factors related to the content and structure of the CSS curriculum, teachers' autonomy in choosing a curriculum, teachers' access to resources, and their relationship with and support from program administrators.