Controlling IT manager access?

I am the business manager for a small business and have been doing all
accounting and IT functions myself. I am considering hiring someone
to take on the majority of these tasks so will need this employee to
perform domain admin functions but I need to restrict access to
payroll and other HR files. Suggestions on how best accomplish this
would be greatly appreciated. The LAN is made up of a single server
running Server 2003 Standard SP2 with 11 XP Pro SP2 PC's.

TIA

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BrianG
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