I have an existing polygon feature class with about 30 attribute fields. I would like to append another 20 fields from an existing table in the same file geodatabase. Can this be done using an out-of-the-box tool? This is not a problem when creating a new feature class; in this case I would use the Import button on the Feature Class Properties:Fields tab. Now that my feature class contains records (as well as a subtype field with subtypes, in case this makes a difference) the Import button is unavailable (dimmed).