Companies are increasingly concerned about the security of their documents. To this end, Word provides a number of features that offer varying levels of security. If you store your documents on network servers, you can combine Word's security features with the access restrictions built into your network operating system to tailor a security approach that meets the needs of your organization.
Word's security features include
Password-protected, 40-bit encryption
Document protection that limits the changes that can be made to a document
Some macro virus protection
Word makes it easy for users to encrypt documents using 40-bit encryption, the strongest encryption that may be legally exported. ...