storing and then displaying HTML for update

I'm writing a php application which includes accepting and storing HTML for routine display by the application. All of this seems to be working fine. However, I also want to display the raw HTML for administrators of the system to update as necessary. I just discovered that this does NOT seem to be working. When I attempt to put this raw HTML into a textarea field on my page, I get unpredictable results. There must be a way to do this, since I've seen this done in other php applications. Can someone tell me how to do this? Is there some way to do this other than to put all of this raw HTML into a textarea field, or is there some technique for getting it successfully into a textarea field? I'm stumped right now. Thanks for any help anyone can give me. Rod