Jim,
Thanks. As you correctly surmised, I am an unsophisticated user of Acrobat Pro (Mac 9.4.6) and did not know HOW to do that. But your response let me to the Properties selection on the File Menu.
Once there it took me a little while to figure out that I could use the Password Security under Security Method WITHOUT requiring all people receiving the file to know the password.
Unfortunately it is difficult to find help on this issue, because all searches I tried to do led me to printing difficulty problems, and none to how to make it happen.
Thanks again for your help in leading me in the right direction.
Mike