Build a query, then build your Combo Box based on that query.

Are the two tables related in any way?

The two tables have same type field but different data.   If i build a query I would have two different fields.  I need the Combo to pull what looks like one field but from two tables.

Union Query

Union query is the right way here.  The two tables don't even need to have the same structure, nor column names, nor column count.  And the two columns being "unioned" don't even need to be of the same data type -- the union query can convert them to the same data type for you.

For instance, if Table1 contains an integer field called MyNum, and Table2 contains a text field called MyText, then this union query will put them together like magic:

    SELECT MyNum AS field1 FROM Table1
    UNION
    SELECT MyText AS field1 FROM Table2