This study examined claims that teachers' years of teaching experience correlate to teachers' effectiveness. The assumed experience-effectiveness relationship was used to support the Government of Ontario, Canada's policy decisions concerning teacher hiring practices. This study critically examined sources cited in the policy report and reviewed other research on teacher effectiveness. Findings indicate that the relationship between total years of experience and teacher effectiveness, as measured by student achievement gains, is complex, nuanced, and nonlinear. The conclusion is that decisions based on assumptions that the relationship between experience and effectiveness is direct and linear are simplistic and lead to less than optimal policy.