Security settings and access privileges for a PDF file cannot be set in Reader; however, they can be set using Adobe Acrobat software. With security settings, authors can define who can open, view, print, copy, or modify a document. These capabilities help organizations protect the confidentiality of sensitive information. With access privileges, authors can define a password that users will need to open the document, or they can use a certificate ID to encrypt the document so select recipients can open it by entering their own, unique certificate IDs.