See http://www.slipstick.com/calendar/scheduleall.htm for various solutions.

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Sue Mosher, Outlook MVP
Author of
Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx
> How can I merge 8 user controlled calendars into one shared calendar
> display?
>
> Each user is to keep own calendar up to date but all user appointments
> should be merged into either a single calendar or a side by side display.