A number of recent policy initiatives, including NCLB's highly qualified teacher provisions, have sought to improve the qualifications of teachers and their distribution across schools. Little is known, however, about the impact of these policies. In this study, we use population data on teachers and schools in Illinois to examine changes in the level and distribution of teacher qualifications from 2001 to 2006. We find that schools in Chicago, especially those serving the highest percentages of low-income and minority students, experienced the greatest improvements in teacher qualifications during the period. Although positive changes in teachers' academic qualifications in Illinois were not restricted to the state's largest urban district, the results were more mixed in non-Chicago locales. The employment of new teachers with stronger academic skills and reductions in the employment of new and experienced teachers without full certification contributed to these outcomes. Our results suggest that a number of policy initiatives, including NCLB's highly qualified teacher provisions, the introduction of alternative route programs in Illinois, and Chicago's comprehensive efforts to recruit talented new teachers, together had a positive impact on the level and distribution of teacher qualifications. Even so, Illinois has a long way to go before disparities in teacher qualifications across its schools are eliminated. (Contains 5 tables, 7 figures and 10 footnotes.)