Folder permissions in XP

Hi, how do I give a certain user read/ write permissions to a folder in Windows XP professional??

In 2000 I simply right click the folder, click the security tab and then add the user I want to give access to the folder and check off the appropriate settings (read/ write/ execute etc)

The security tab has disappeared in XP and has been replaced with 'Sharing'. I can't find anywhere where I can give specific users access to the selected folder...

Thanks for any help in advance
Cheers
MarkusJ

From MyComputer got to:

Tools>Folder Options> View

go down and remove the tick from "Use Simple File Sharing (Recommended)'

By the way you must have the drive formatted as NTFS.