This paper describes the knowledge transfer strategies used by Cancer Care Ontario, in partnership with 14 regional cancer centres, with the aim of improving the cancer stage data in Ontario. As physicians are directly responsible for the documentation of cancer stage, the success of this initiative is directly related to improvements in physician documentation practices. Knowledge transfer strategies included the use of local opinion leaders, educational sessions, and audit/feedback loops. Evaluation results reveal an increase in the provincial cancer stage data from 30 to 68%. The information presented here will be of interest to organizations implementing practice changes requiring physician engagement.