Researchers collect data from both individuals and organizations under pledges of confidentiality. The U.S. Federal statistical system has established practices and procedures that enable others to access the confidential data it collects. The two main methods are to restrict the content of the data (termed "restricted data") prior to release to the general public and to restrict the conditions under which the data can be accessed, i.e., at what locations, for what purposes (termed "restricted access"). This paper reviews restricted data and restricted access practices in several U.S. statistical agencies. It concludes with suggestions for sharing confidential social science data.