The diversity of teaching professional development (PD) programs that occurred over the last few decades merits our collective attention to assess the impact of these programs over time. In general, the goal of PD programs is that participants continue to practice what they learn in the long term. However, we do not know the degree to which the outcomes of these programs were achieved and ultimately persist. We tracked postdoc participants from the Faculty Institutes for Reformed Science Teaching (FIRST) IV program into their current position as early-career faculty at institutions across the United States. We assessed their teaching approaches, practices, and student perceptions of the learning environment over 6-10 years. Additionally, the FIRST IV faculty were paired with colleagues of similar status in the same departments. We found that professional development outcomes from the FIRST IV program persisted over time and across a significant career transition, from postdoc to faculty. These participants not only maintained their student-centered practices, but were significantly more student-focused than their peers. Lastly, we found that faculty approaches to teaching were correlated with observed teaching practices in the classroom for both groups of faculty. These results provide compelling evidence for the success of the FIRST IV program and the long-term persistence of professional development outcomes.Introduction: