High-quality teaching is the most significant school-related factor in helping students make significant gains in learning or achievement. Students who have effective teachers year after year routinely make more progress than other students. This is why every child must experience great teaching every day. For this to occur, teachers must have opportunities to learn together, collaborate, use readily available data and examples of student work, and pool their collective expertise around their most urgent challenges. The National Staff Development Council (NSDC) is working with states and districts to create the infrastructure necessary to promote more effective and meaningful professional development. NSDC sets rigorous standards for high-quality professional development; benchmarks policies and practices against research to ensure that schools are using the most effective approaches; and assists states and districts in measuring how well they meet the standards. NSDC's challenge is to help schools--and the teachers and administrators who run them--take action to ensure that good practice becomes everyday practice in every school. This report is an attempt to show the full scope of the work NSDC does and to provide some insight into the status of and progress in the field.