Abstract: A system and method for controlling the downstream preservation and destruction of electronic mail by encrypting the electronic mail and limiting access to the encrypted file based on registration of recipient e-mail addresses, and detection and restriction of output functionality available to the recipient. The registration procedure limits access to recipients included on an access control list, who receive a pre-configured reader and then authenticate their e-mail address to the reader via a known SMTP Server. The sender of an e-mail is provided with a dialog for determining the limitations on access to the e-mail by the recipient: whether the e-mail is to be inaccessible after a certain period of time, whether a recipient may copy or print the e-mail and/or its attachments, or whether a password is required to read the e-mail. These limitations comprise an access control policy applicable to the e-mail, the pre-configured reader being adapted to decrypt the e-mail and apply the policy.