The research team for this study consisted of a prime contractor, American Institutes for Research (AIR), and three subcontractors, MDRC, REDA International, Inc., and Westat, Inc. None of these organizations or their key staff has financial interests that could be affected by findings from the Middle School Mathematics Professional Development Impact Study. No one on the 10-member Expert Advisory Panel, convened by the research team annually to provide advice and guidance, has financial interests that could be affected by findings from the evaluation.