Who can read this document

I have discussion database with a lot of documents in it, and I need to grant access rights to one user to all documents using Document Properties - security tab – Who can read documents. Hence, I need to click to every document and grant rights. Is there any way to define rights by picking all documents (or part of them).Thx a lot

Subject: $Readers

you can run an agent to add the $Readers item to the documents. If the item already exists you can add names to it using an agent as well.