The Reading First Program is a central element of the No Child Left Behind legislation (No Child Left Behind Act, 2001). It builds on findings reported in a national consensus report (NICHD, 2000), about proven strategies to reduce the prevalence of reading difficulty in the early grades in order to help children read at or above grade level by the time they reach third grade. The program provides resources to schools for professional development, for purchasing reading programs/materials, for assessments of students, and for salaries of reading coaches who can help classroom teachers. Reading First departs from historical precedent in its reach into the content of instruction. Traditionally, the federal education agency has been focused on issues of access, and determination of actual curriculum content has been left to states and localities. The legislation contained a savvy blend of federal guidance for local decision-making; it did not endorse any reading materials or professional development or assessments, but rather articulated the procedures states and districts were required to use as they made local decisions about which districts and schools to fund as well as which specific tools those districts and schools selected help to implement the program. The Reading First Impact Study was designed to assess the impact of the Reading First Program on two core domains: classroom reading instruction and student reading achievement. This paper will summarize the methods used and the study's findings on the two questions of program impact. (Contains 4 exhibits and 2 footnotes.)