Black flats have become the off-duty shoe of choice for many celebrities, in styles from classic ballet flats to Mary Janes and elasticated slippers. Pick a detail you like and wear it with everything. Zimmermann's knotted Carousel ballerinas, Loewe's cut-out Petal flats, Le Monde Beryl's buckled Claudia flats and Jil Sander's rubber-trimmed satin Elbe flats are all strong options.

A Mary Jane adds a strap and a little charm. Burberry's Robin Check Mary Janes and Alaïa's criss-cross embellished suede flats both suit Stouls's orange leather Winona skirt, and Dôen's cream cropped cable-knit cardigan softens the look.

The classic flat looks best with the simplest clothes. Church's black Sheila Mary Jane flats and Mother's light-wash Newbie Skimp jeans pair with Agolde's cream layered T-shirt, and Stella McCartney's taupe Falabella mini bag completes it.

Black flats with tailored trousers is one of the smartest workday outfits there is. Jimmy Choo's shearling-trimmed suede Margot flats and The Row's black Coleman trousers meet Khaite's army green Armair blazer and Dries Van Noten's crisp white poplin shirt.

A pointed satin flat works with an evening dress more often than you might think. Christian Louboutin's black satin Erozeena flats and Aflalo's white polka-dot halterneck Nourin maxi make a playful pair, and Staud's snake-effect clutch and Completedworks' red beaded earrings add the finish.

Black flats are one of the few shoes that look right in almost every setting. If you take one thing away, let it be that a pointed or almond toe looks dressier than a round one, and that small change decides whether the shoe can go to dinner. A strap or buckle adds interest without making the shoe harder to wear. We would skip very thin, unstructured slippers if you walk a lot, since they give little support. A leather sole with a bit of padding is worth looking for, and one good pair will do more work than several flimsy ones.