Starting in Office 2007, Microsoft provided the capability to create PDFs directly from all the Office programs. This was a boon for Office users as we no longer needed a licenced version of Acrobat or some third party product to create PDF files. Put the PDF or XPS button on the Quick Access Toolbar and a single click opens the dialog box to name the PDF.
Most people have discovered this and use the feature regularly. Have you discovered, though, that in Word 2010 and Word 2013 you can password protect the PDF?
In the Publish as PDF or XPS dialog box, there is an Options button at the bottom of the dialog box. Click on it and then select the last check box at the bottom of the dialog box: Encrypt the document with a password.
Click on OK and you will be prompted to enter a password twice. Minimum number of characters is six. When you are finished, click on the Publish button to create the PDF.
When you open the PDF you’ll be prompted for the password. Oddly, this option seems to only be available in Word 2010 and Word 2013.