Spurred by the federal government’s Teacher Incentive Fund and Race to the Top grant programs, policymakers appear increasingly inclined to utilize measures of student achievement to inform teacher performance evaluations and high-stakes teacher personnel decisions; however, there is no universally accepted method for estimating teacher performance based on student achievement.  In this paper, we use statewide data from North Carolina to evaluate different methodologies for translating student achievement results into teacher performance and explore the extent to which these various methodologies yield different teacher effectiveness estimates.  While we find that most teachers are rated similarly regardless of the model used, teachers with a high percentage of disadvantaged students (measured by free/reduced price lunch status, disability status, and prior-year achievement) tend to have different ratings across different models.