I have a table TblEqup & TblHardware. For various pieces of equipment they can have the same piece of hadware.

Ie. EquipSerialNumber 78 & 79 can belong to 0019 (78, 0019) (79, 0019)

I want to be able to establish this relationship so I can have (78 & 79, 0019) and not have to do duplicate entry, but am not sure how. I've attached a screen shot of my attempt. :eek:

Can you define/describe equipment and hardware and how they differ?
I don't understand exactly what you are dealing with, but it seems there is a table missing.
That table, in my limited view if what you are dealing with, would be a junction table between Equipment and Hardware--- lets call it tblXXX ( you may have a name for it) and would have a compound primary key of EquipId + HardwareID.

Just my 2 cents without more info.

I think it's the junction table the OP is trying to avoid but what is normalisation without that juntion table?

You can have that convenience if you were using Access 2007 or 2010 but it seems you're using an older version. This would be utilising what is called a multi-value field.