While policymakers have tried to improve teacher workforce effectiveness by raising certification requirements, research shows that credentials correlate little with teaching excellence, as measured by student performance. School districts do little additional screening and commonly award tenure after two or three years regardless of performance. The most effective teachers receive no incentives to work in the poorest districts. In a discussion paper for The Hamilton Project, Robert Gordon, Thomas J. Kane, and Douglas O. Staiger propose a new five-point reform that would address these difficulties. Their proposals would increase the pool of potential teachers, make it tougher to award tenure to those who perform least well, and reward effective teachers who are willing to work in schools serving large numbers of low-income, disadvantaged children. Their recommendations: (1) Reduce Entry Barriers; (2) Make it Harder to Award Tenure to the Least Effective Teachers; (3) Give Bonuses to Highly Effective Teachers Willing to Teach in Disadvantaged Schools; (4) Establish Systems to Measure Teachers' Job Performance; and (5) Track Student Performance and Teacher Effectiveness over Time. This policy brief summarizes the full discussion paper, which may be found at ED495041.