In 2010 twenty-three Maori medium schools were given the opportunity for professional development with the Draft Nga Whanaketanga Rumake Maori: Pangarau (NWRM) (National Standards Maori Medium: Mathematics. The study provided a unique opportunity to listen to teachers' views about their professional development as they sought to implement national standards for mathematics education. Data was obtained from teachers in three schools to help identify key factors that they considered influential for their professional growth and development. The findings show that effective leadership, the development of high quality professional relationships between participants, appropriate resourcing and the serendipitous nature of professional learning, all contributed to the implementation of this government mandate.