It's not possible to do that with a simple validation formula. You'd need to put code in the Item_Send event handler to get the number of days with DateDiff() combined with some addition or subtraction based on the day of the week to account for weekends.

--
Sue Mosher, Outlook MVP
Author of Configuring Microsoft Outlook 2003
http://www.turtleflock.com/olconfig/index.htm
and Microsoft Outlook Programming - Jumpstart for
Administrators, Power Users, and Developers
http://www.outlookcode.com/jumpstart.aspx

"Aggie G" wrote in message ...
I need help writing a validation rule. In the form that I am creating, there
is a turn around time (ETA) of at least 10 business days. I would like to
write a validation that tells the user to enter another date if the date they
entered (Date Needed) is less than 10 business days away from the request
date (Request Date). How would I write this? The form is a message form.