Highly Accomplished Teachers (HATs) think deeply about skilled pedagogy in ways that illuminate its complexity and the challenges of pedagogical change. The sophistication, breadth, and depth of their thinking often goes well beyond the way that teachers and their responses to professional development (PD) are typically positioned in the extensive, and often quite pessimistic literature on teacher PD. This study extends our previous research with a cohort of HATs immediately following their participation in an intensive PD programme, where we reported how they took ideas from the programme and extended and amplified them by exerting agency and high degrees of professionalism. Our current study reports research with the same cohort 2 years post-PD as they sought to introduce ideas inspired by the PD within their schools. While there were some clear successes, some of their ideas challenged existing thinking and practices in ways that school leadership did not expect. Thus, they encountered barriers that in some cases they were able to navigate and overcome. This paper foregrounds the new complexities of both pedagogy and change that flowed from the HATs' ideas as well as how they exerted their professionalism to tackle these.