Some of the most powerful influences on the development of teacher efficacy are mastery experiences during student teaching and the induction year. Bandura's theory of self-efficacy suggests that efficacy may be most malleable early in learning, thus the first years of teaching could be critical to the long-term development of teacher efficacy. Yet few longitudinal studies exist that track efficacy across these early years. This study reports changes in teacher efficacy from entry into a teacher preparation program through the induction year. Multiple quantitative assessments of efficacy were used including Gibson and Dembo's Teacher Efficacy Scale, Bandura's assessment of Instructional Efficacy, and an instrument designed to reflect the specific context and goals of the preparation program studied. Results indicated significant increases in efficacy during student teaching, but significant declines during the first year of teaching. Changes in efficacy during the first year of teaching were related to the level of support received.