Vintage Butterick 8861, literally

A fairly literal interpretation, I admit. I doubt the original was meant to be made in comfy cotton elastane though (think thick leggings or yoga pants material). The ribbon ripples like that when I move, but looks worse in the photos than in real life I think (hope).

Black hides the front bodice pleats, but they're there.

I sewed the front bodice and skirt pieces together, then the back bodice and skirt, then joined them at the shoulders so I could sew the under sleeve and side seams in one pass. I knew I'd have to remove the ease making it in a stretchy knit, and it was easy just to whoosh it through the overlocker to remove the excess.