This paper offers an insiders' perspective on the large-scale, system-wide educational change undertaken in Ontario, Canada from 2003 to the present. The authors, Ministry and school system leaders intimately involved in this change process, explore how Ontario has come to be internationally recognized as an equitable, high-achieving, and continuously improving jurisdiction (Brochu et al. in Second report from the 2009 programme for international student assessment. Council of Ministers of Education, Canada, Toronto, 2011; Mourshed et al. in How the world's most improved school systems keep getting better. McKinsey & Company, New York, 2010; OECD in Strong performers and successful reformers in education: lessons from PISA for the United States. OECD, Paris, 2010). The narrative of improvement in Ontario presented here was developed out of systematic interviews with Ministry and School Board leaders' experiences of the literacy improvement strategy, and informed by document and data analyses. It addresses the historical and political context of Ontario's change efforts, the shifting understanding of teaching and learning in the province, the essential respect for the professionalism of educators, the structures that facilitated the change, and concludes with key characterizations of the present culture of education in Ontario. While the paper focuses on the elementary literacy strategy, its wider objective is to outline the collaborative approach to shifting pedagogical practice that has opened the ceiling for what a public education system is capable of achieving by fostering local ownership of change while raising the floor by setting high standards for literacy achievement for all students.