I have two tables I've joined together. After the join I added a defined field (Edit function). I checked the Define and it had no errors, then I saved the procedure. The defined field is not showing up in my list of fields in Object Inspector in Report Painter. It is showing up in my code:

DEFINE FILE BEN_ACT
MEDPLAN1/A4=EDIT ( MED_PLAN, '$$$$9999$');
END

What am I doing wrong?

When you join 2 files the first joined file is the one you must reference in the DEFINE.

ie.

JOIN flda IN BEN_ACT TO ALL flda
IN cross-referenced file AS J1
END

DEFINE FILE BEN_ACT
MEDPLAN1/A4=EDIT ( MED_PLAN, '$$$$9999$');
END

If BEN_ACT if the cross-referenced file the MEDPLAN1 field will not appear in the field list.