Security: encrypting PDF documents
More security: PDF document encryption can be accomplished relatively easily and you can basically choose between two different types of encryption, namely using password or certificate security.
An appropriate level of protection is recommended when exchanging particularly sensitive or mission-critical documents. The security offered by conventional transfer methods - such as sending by e-mail or storing on a server - is inadequate for effectively safeguarding your files against unauthorized access. This is why file-level encryption, such as that provided by Adobe Acrobat Pro, is vastly more reliable.