Once you have finished your screenplay you are going to want to protect it. This includes registering it at the U.S. copyright office and with the Writer’s Guild of America. Both of these sources cost money, but they will help to establish your exact work as a unique piece. They cannot, however, protect all of the story elements or themes in your screenplay. It is best to do this for the first draft on, especially if you are going to be showing early drafts to industry professional and critics. Remember that copyrighting your script gives you more control on how much security you want on your script and will give you a more comprehensive and longer period of protection.