This longitudinal study of six first-year teachers focused on conceptualizations of inquiry-based pedagogy, self-efficacy for inquiry-based teaching, and its actual enactment. Data included a self-report survey of self-efficacy for inquiry-based instruction, individual interviews at the beginning and end of the year, and five distributed classroom observations. At year's end, self-efficacy for inquiry teaching declined, as did frequencies of concepts teachers used to describe inquiry enactment. Inquiry descriptions reflected a set of interrelated procedures more than inquiry as conceptual knowledge. Novice teachers were observed least enacting pedagogical actions that required enabling students to communicate findings and the most in student engagement; however, over time frequencies of student engagement declined. Consistent patterns were observed between shifts in self-efficacy and inquiry enactment and shifts between self-efficacy and conceptualizations of inquiry enactment. We found beginning steps toward links between teacher's conceptualizations and classroom practice.