FileMaker fields can shrink, but they can't expand to fit the data in them. And the change is only visible when in preview mode, on printed hard copy or in a PDF--so it isn't likely to be a useful feature inside your tab control. YOu can add a scroll bar to the description field if you wish. On the other hand, if you don't add the scroll bar, you can click into the field and see it expand to display the full field contents. And you can set a tooltip to display the full field contents when you hover the mouse over it.
Thanks, so its not like Excel with word wrap where the cells just keeps getting bigger, too bad.