ANSWER:

Because you might not be sure of exactly how far the target element is from the current element, and assuming you only want to find one target element:

$(this).closest('.modal-window');

• parent() selects the immediate-parent element of $(this), returns a jQuery object of one, or none.
• parents() selects all matching ancestor elements of $(this), returns a jQuery object of one, none or many.
• closest() selects the first element matching the selector in the DOM ‘tree’ above the $(this), returns a jQuery object of one, or none.

by David Thomas from http://stackoverflow.com/questions/10266582