Ok. I've got this almost working, but I still have one problem. To start with, here is the code I am using:
SELECT SrvcRest.*, ReRoutes.[Bulletin #], ConcatRelated("[Bulletin #]", "SrvcRestandBulletins", "SrvcRest.ID = " & SrvcRest.[ID])
FROM SrvcRest LEFT JOIN ReRoutes ON (SrvcRest.EventDate...