Depending on the interface you are using, it may be possible to adda field. If you are using the Btrieve API, there's really isn't a way to add a field to the file without recreating the file but even that can be done in code. However, this wouldn't update the DDF. You might be able to use DTI or DTO to recreate the entry in the DDF though. If you are using ODBC, you should be able to use an Alter Table statement to add a field and that would update the DDF.