This is such a great dress that I'd be wearing so often if I could fully zip it up!  Size marked medium but fits current size small.   PLEASE see the second photo for measurements as there is no give.   Trust me,  I've tried! 

Convenient side zip and a waist tie that can go in the front or back.  

This dress is so hard to find trust me as I've been looking for the size large myself.   Excellent condition!