The construction should be:
{If {MERGEFIELD Title} = "Ms." {MERGEFIELD Name} {MERGEFIELD Spouse}}
You must use Ctrl+F9 for each pair of field delimiters { } if you insert
this directly from the keyboard
Otherwise, use the If...then...Else word field, select the Title mergefield
in the "Insert Word Field: IF" dialog, enter Ms. in the Compare to: control
and put A in the Insert this text: control and B in the Otherwise insert
this text: control. Then click on OK.
Then in the Document, press Alt+F9 to display the field codes, select the A
and then for the list of merge fields, select the Name field. Then select
the B and from the list select the Spouse field. The A and the B should
then be replaced by those fields so that you end up with the above field
construction.

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Hope this helps
Doug Robbins - Word MVP
> I would like to create a condition in which a true value
> of a certain field would print the contents of a
[quoted text clipped - 8 lines]
> Thanks,
> Julie