I do believe that I had promised (way back when) to show how I put a loop and button closure on the inside of a skirt with a facing finish at the waist. One really does need some "insurance" at the top of the zipper, but with this style, a hook and eye closure ends up poking into your side (ouch!). So - here goes. If my explanation makes no sense - hopefully there are enough pictures to illustrate.
Oh, right - this only works with an invisible zipper, which seems to be my zipper of choice on skirts and dresses these days. Zipper is in at this point, and you're ready to sew on the facing.
Pin the facing along the top edge of the skirt, wrapping the seam allowances to the wrong side of the skirt.
And there you have the "ouchless" method of making sure that your skirt is going nowhere, should your zipper fail.