show the "record source" for the combo box in question.

The row source is:  SELECT [CountyNamesUsedQ].[County], [CountyNamesUsedQ].[CountyName] FROM CountyNamesUsedQ ORDER BY [CountyName];

Are you saying you're trying to filter by CountyName instead of County, but County is the bound field? You can use ComboBoxName.Column(1) to get the second fields value

The County should be named CountyID as it's the numerical value stored in the table underlying CountyNamesUsedQ.  My continuous form shows the string value (name) that corresponds to the bound column, but because the stored value is numeric, I'm not getting any matches.

Sorry can you include some images then? This is confusing me.

If the table the form your filtering on is storing the number, you could just filter off the combo box how it's setup, the bound field is 1 which is the number field (CountyID). If the table the form your filtering is storing the text value you can use Column(1) to get the text value of the combo box (CountyName).

Are you doing this with VBA or the "wizard" making a search combo box?

Thanks for your help, Adam.  I've been pulled into another project and doubt I'll be able to respond until tomorrow.  Please don't take my delay as a lack of gratitude on my part.

I found the problem.  The VBA code was trying to match CountyName (text) with the CountyNameID (numeric). Once I set the call to the correct field everything worked fine.  Thank you again for your help.