Fire Place Marble or Granite Installation

I have installed a fireplace surrounded by drywall. How do I attach and secure the marble or granite around the fireplace and with waht materials? Please advise, thank you.

They are normally attached with Thinset and stress crack membrane but I am hesitant to to leave it at that.

The installation method should be verified to comply with the heat output of your fireplace unit for safety reasons. Your fireplace kit should come with specific instructions for the type of materials and how they should be attached due to the amount of heat that unit is designed to produce.

General how-to:
http://www.ehow.com/how_4828716_install-granite-around-fireplace.html