There are more options than I can list in a single post. One option is to use one layout for data entry for new records and a different one for accessing the data when you don't want the user to be able to edit data. The second layout can be set up so that users cannot enter any of the fields while in browse mode. This can be set up by clearing the "browse" check box for each field in the behavior settings on the Inspector's data tab. An "edit" button can switch layouts to take the user to the layout where editing is permitted.
And there are ways to design your database so that different users have different levels of access to different groups of records using Manage | Security.
And Field validation rules can be set up so that when a single "lock" field is given a value all changes to the fields are rejected until the value in that lock field is changed.
And the method I mentioned in my first post using global fields is also an option that can be used.
Ok! I am not really familiar with global fields and i am definitely curios about it. I have not tried the Manage and Security yet. I will look that up right now. I will try some of these info that you gave out too. Thanks so much for your help.
For more on the Manage | Security method, see "Editing record access privileges" in FileMaker Help and check out this particular sub section: "Entering a formula for limiting access on a record-by-record basis" for a description of how to set this up.