We provide a comprehensive analysis of a Texas policy that relaxed teacher licensing requirements and created a large for-profit training industry. Using detailed administrative data, we show that for-profit-trained teachers have higher turnover and lower value-added than standard-trained teachers. But the policy significantly increased the supply of certified teachers, reducing schools' reliance on uncertified teachers with even worse outcomes. Exploiting variation in policy exposure across schools, we find a zero net impact on student achievement due to these offsetting forces. Thus lower licensing requirements improved access to teaching and reduced training costs without harming students. [Research for this report was supported by a Cornell Center for Social Sciences Grant.]