An analysis of all cases filed in federal district courts, bankruptcy courts, and courts of appeals in 2006 revealed that 0.2% of civil cases, 1.6% of criminal cases, 16% of magistrate judge cases, 34% of miscellaneous cases, and 0.1% of appeals were sealed approximately two years after filing. Cases filed in bankruptcy courts are virtually never sealed. This report, prepared for a sealed case subcommittee of the Judicial Conference's standing Committee on Rules of Practice and Procedure, describes why and how cases were sealed.