PrefaceFrustrated by a history of low student achievement and financial crises, the state of Pennsylvania took charge of the Philadelphia public schools in 2002. Within months of the takeover, a newly created School Reform Commission had launched the nation's largest experiment in the private management of public schools. The commission, which replaced the local school board, turned over 45 elementary and middle schools to seven private for-profit and nonprofit managers. In addition, the school district, under a new CEO, implemented wide-ranging and ambitious reforms in district-managed schools. This monograph examines student achievement outcomes for the district as a whole and for privately managed and district-managed "restructured" schools during the first four years after the takeover (through spring 2006).