<p>This study explores how a physics professor’s understanding of teaching for conceptual change evolves through sustained collaboration with a science education professor. Using a phenomenographic case study approach, we analyze shifts in the professor’s conceptions over time, revealing key transitions from viewing student misconceptions as barriers to recognizing conceptual frameworks as bridges for learning. Findings highlight the role of cognitive conflict, conceptual resources, and metacognitive engagement in shaping pedagogical change. The study contributes to understanding faculty development in STEM education, emphasizing the impact of interdisciplinary collaboration on instructional transformation. Based on these findings, future research and policy recommendations are proposed.</p>