I know access doesn't support full outer joins, but I've read that it can emulate them through a combination of other joins.

I've got 3 queries with 2 common columns which I'll call ColA and ColB. None of the other columns are common.

It's possible for there to be a record in one query with no match in the others. In this case I still need the record to show up with blanks/nulls in the other two queries.

It's hard to help without knowing more about the table definitions. Wikipedia provides a good example on how to emulate a FULL OUTER JOIN. See: Join (SQL) - Wikipedia, the free encyclopedia)

It's ok, I found a workaround to reduce it to two tables.