See http://www.slipstick.com/exs/permissions.htm for tools that can help set
the necessary permissions to accomplish this.

Signature
Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> Currently the default on Outlook Calendar is to hide all calendar
> appointments. The default should be to allow all users to see all calendar
> appointments, unless the users has specifically opted out. Otherwise it
> makes
> it very difficult to figure out if someone is in an important meeting or
> not.