Hi,
Name the range containing the emploee names
Then refer to the range name in your data validation

That is the only way you can refer to a range outside of your worksheet
using data validation

For more help see:
http://www.contextures.com/xlDataVal05.html

"J. Osborne" wrote:

Scenario: Sheet A contains employee last name, first name, etc. Sheet B I
need to assign an employee to a project so I want to ensure I only select a
first and last name that is available in Sheet A. How do I do that?

I need to complete a validation with a list; however, my list is contained
on a separate Excel Worksheet Tab than where I'm creating the validation
formula. Excel indicates comes back with an error message that this cannot
be done that the list must come from within that specific worksheet.

Is there a way around this or can I use a different function? I'm not
looking to return a value so I'm not looking to perform a look up function.