Folder level permissions in Sharepoint 2003

Is there a way to apply folder level permissions on Sharepoint 2003. I have a request to lock down a folder so only two upper level management users can access the documents. So far I have not been able to find a way to lock down the folders like NTFS. I can make a link to folders outside of sharepoint and lock those down but not from inside sharepoint...is this a limitation of sharepoint 2003?